US5825664A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Field-mounted control unit
Assignee: Rosemount Inc
•
Filing: 1995-06-07
•
Granted: 1998-10-20
•
Expires: 2015-06-07
Abstract
Abstract A smart field-mounted control unit, for controlling a process, receives signals and sends a command output over a two-wire circuit which powers the control unit. An input section receives the signals, which can be instructions representative of commands or instruction sets, process variables sensed by external control units or setpoints representative of a desired process state. The instructions are representative of a control requirement of the process and adjust a controlling section in the control unit to generate the command output in conformance with the control requirement. The command output can be a function of the difference between the process setpoint and a process variable, or a function of a linear combination of a process variable and its calculated time integral and time derivative functions. A sensing section in the control unit can sense and scale a process variable for generating the command output as well. The control unit can include a regulator section, controlled by the command output, which regulates application of a mechanical, hydraulic, pneumatic or electromagnetic force applied to the process.
Inventors
- 👤 Jogesh Warrior
- 👤 Vincent C. Jacobson
- 👤 Kelly M. Orth
- 👤 Craig R. Tielens
- 👤 Jane Barbara Lanctot
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:18
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/418; G05B19/4185; G05B15/00; G05B15/02; G05B2219/00; G05B2219/30; G05B2219/31; G05B2219/31119; G05B2219/31154; Y; Y02; Y02P; Y02P90/00; Y02P90/02
Claims Analysis
Total Claims: 307
Claim 1
Independent Claim
172 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a process signal from the two wire circuit; a process variable sensor which provides a sensed process variable; and control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the sensed process variable and a previous value of the command output.
Claim 2
Dependent Claim
172 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a process signal from the two wire circuit; a process variable sensor which provides a sensed process variable; and control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the sensed process variable and a previous value of the command output.
Claim 3
Dependent Claim
15 words
The control unit of claim 1 wherein the command output comprises a 4-20 mA signal.
Claim 4
Dependent Claim
14 words
The control unit of claim 1 wherein the command output comprises a digital signal.
Claim 5
Dependent Claim
15 words
The control unit of claim 1 wherein the process variable sensor is in the housing.
Claim 6
Dependent Claim
17 words
The control unit of claim 1 wherein the process signal is representative of a redundant process variable.
Claim 7
Dependent Claim
27 words
The control unit of claim 1 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 8
Dependent Claim
27 words
The control unit of claim 1 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 9
Dependent Claim
27 words
The control unit of claim 1 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process variable.
Claim 10
Dependent Claim
22 words
The control unit of claim 1 wherein the process signal is representative of an instruction to direct operation of the control unit.
Claim 11
Dependent Claim
27 words
The control unit of claim 1 wherein the process signal is representative of a coefficient of a term of an instruction set stored in the control unit.
Claim 12
Dependent Claim
35 words
The control unit of claim 1 wherein the process signal is representative of a setpoint and the control circuitry adjusts the command output as a further function of the setpoint and the sensed process variable.
Claim 13
Dependent Claim
25 words
The control unit of claim 1 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 14
Dependent Claim
31 words
The control unit of claim 1 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 15
Dependent Claim
28 words
The control unit of claim 1 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 16
Dependent Claim
29 words
The control unit of claim 1 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 17
Dependent Claim
71 words
The control unit of claim 1 wherein the command output, q K , is generally in accordance with the equation: ##EQU2## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 18
Dependent Claim
38 words
The control unit of claim 1 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 19
Dependent Claim
14 words
The control unit of claim 1 wherein the function further comprises a PI function.
Claim 20
Dependent Claim
14 words
The control unit of claim 1 wherein the function further comprises a PD function.
Claim 21
Dependent Claim
14 words
The control unit of claim 1 wherein the function further comprises a PID function.
Claim 22
Dependent Claim
19 words
The control unit of claim 1 including a storage element for storing the previous value of the command output.
Claim 23
Dependent Claim
25 words
The control unit of claim 1 wherein the process signal is representative of a command which selects an instruction set stored in the control unit.
Claim 24
Dependent Claim
29 words
The control unit of claim 22 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 25
Dependent Claim
26 words
The control unit of claim 22 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 26
Dependent Claim
31 words
The control unit of claim 22 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
Claim 27
Dependent Claim
174 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; and control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint and which is a function of a previous value of the command output.
Claim 28
Dependent Claim
174 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; and control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint and which is a function of a previous value of the command output.
Claim 29
Dependent Claim
15 words
The control unit of claim 26 wherein the command output comprises a 4-20 mA signal.
Claim 30
Dependent Claim
14 words
The control unit of claim 26 wherein the command output comprises a digital signal.
Claim 31
Dependent Claim
15 words
The control unit of claim 26 wherein the process variable sensor is in the housing.
Claim 32
Dependent Claim
29 words
The control unit of claim 26 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit representative of a redundant process variable.
Claim 33
Dependent Claim
27 words
The control unit of claim 26 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 34
Dependent Claim
27 words
The control unit of claim 26 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 35
Dependent Claim
28 words
The control unit of claim 26 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 36
Dependent Claim
36 words
The control unit of claim 26 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 37
Dependent Claim
34 words
The control unit of claim 26 wherein the input circuitry is further adapted to receive from the two wire circuit a coefficient of a term of an instruction set stored in the control unit.
Claim 38
Dependent Claim
25 words
The control unit of claim 26 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 39
Dependent Claim
31 words
The control unit of claim 26 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 40
Dependent Claim
28 words
The control unit of claim 26 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 41
Dependent Claim
29 words
The control unit of claim 26 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 42
Dependent Claim
71 words
The control unit of claim 26 wherein the command output, q K , is generally in accordance with the equation: ##EQU3## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 43
Dependent Claim
38 words
The control unit of claim 26 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 44
Dependent Claim
14 words
The control unit of claim 26 wherein the function further comprises a PI function.
Claim 45
Dependent Claim
14 words
The control unit of claim 26 wherein the function further comprises a PD function.
Claim 46
Dependent Claim
14 words
The control unit of claim 26 wherein the function further comprises a PID function.
Claim 47
Dependent Claim
19 words
The control unit of claim 26 including a storage element for storing the previous value of the command output.
Claim 48
Dependent Claim
19 words
The control unit of claim 26 wherein the command output is further a function of the sensed process variable.
Claim 49
Dependent Claim
25 words
The control unit of claim 46 wherein the command output is a further function of a difference between the setpoint and the sensed process variable.
Claim 50
Dependent Claim
32 words
The control unit of claim 26 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 51
Dependent Claim
29 words
The control unit of claim 48 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 52
Dependent Claim
26 words
The control unit of claim 48 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 53
Dependent Claim
31 words
The control unit of claim 48 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
Claim 54
Dependent Claim
114 words
A smart field-mounted control unit for coupling to a two wire circuit, comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the two wire circuit for wholly powering the control unit; a process variable sensor which provides a sensed process variable; and control circuitry in the housing operably coupled to the input circuitry and to the process variable sensor, the control circuitry is adapted to provide a command output for a remote device, the command output in a digital format which is a function of the sensed process variable and a previous value of the command output.
Claim 55
Dependent Claim
114 words
A smart field-mounted control unit for coupling to a two wire circuit, comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the two wire circuit for wholly powering the control unit; a process variable sensor which provides a sensed process variable; and control circuitry in the housing operably coupled to the input circuitry and to the process variable sensor, the control circuitry is adapted to provide a command output for a remote device, the command output in a digital format which is a function of the sensed process variable and a previous value of the command output.
Claim 56
Dependent Claim
19 words
The control unit of claim 52 including a storage element for storing a previous value of the command output.
Claim 57
Dependent Claim
38 words
The control unit of claim 52 wherein the control circuitry is adapted to be coupled to the two wire circuit and the command output is adapted to be transmitted on the two wire circuit for the remote device.
Claim 58
Dependent Claim
39 words
The control unit of claim 52 wherein the control circuitry is adapted to be coupled to a second two wire circuit and the command output is adapted to be transmitted on the second two-wire circuit for the remote device.
Claim 59
Dependent Claim
15 words
The control unit of claim 52 wherein the process variable sensor is in the housing.
Claim 60
Dependent Claim
27 words
The control unit of claim 52 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 61
Dependent Claim
28 words
The control unit of claim 52 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 62
Dependent Claim
31 words
The control unit of claim 52 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 63
Dependent Claim
28 words
The control unit of claim 52 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 64
Dependent Claim
31 words
The control unit of claim 52 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit which is representative of a current mode of operation.
Claim 65
Dependent Claim
36 words
The control unit of claim 52 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 66
Dependent Claim
36 words
The control unit of claim 52 wherein the input circuitry is further adapted to receive from the two wire circuit at least one coefficient of a term of an instruction set stored in the control unit.
Claim 67
Dependent Claim
25 words
The control unit of claim 52 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 68
Dependent Claim
71 words
The control unit of claim 52 wherein the command output, q K , is generally in accordance with the equation: ##EQU4## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 69
Dependent Claim
38 words
The control unit of claim 52 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 70
Dependent Claim
14 words
The control unit of claim 52 wherein the function further comprises a PI function.
Claim 71
Dependent Claim
14 words
The control unit of claim 52 wherein the function further comprises a PD function.
Claim 72
Dependent Claim
14 words
The control unit of claim 52 wherein the function further comprises a PID function.
Claim 73
Dependent Claim
24 words
The control unit of claim 52 wherein the input circuitry receives a setpoint and the command output is further a function of the setpoint.
Claim 74
Dependent Claim
25 words
The control unit of claim 70 wherein the command output is further a function of a difference between the setpoint and the sensed process variable.
Claim 75
Dependent Claim
32 words
The control unit of claim 52 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 76
Dependent Claim
29 words
The control unit of claim 72 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 77
Dependent Claim
26 words
The control unit of claim 72 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 78
Dependent Claim
32 words
The control unit of claim 72 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a specified limit.
Claim 79
Dependent Claim
130 words
A smart field-mounted control unit for coupling to a two wire circuit for controlling a process control loop, comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry receiving power from the two wire circuit for wholly powering the control unit and the input circuitry adapted to receive a command from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry and to the process variable sensor and including at least one instruction set, wherein the control circuitry selects the instruction set in response to the command for providing a command output for a remote device as a function of the sensed process variable.
Claim 80
Dependent Claim
130 words
A smart field-mounted control unit for coupling to a two wire circuit for controlling a process control loop, comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry receiving power from the two wire circuit for wholly powering the control unit and the input circuitry adapted to receive a command from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry and to the process variable sensor and including at least one instruction set, wherein the control circuitry selects the instruction set in response to the command for providing a command output for a remote device as a function of the sensed process variable.
Claim 81
Dependent Claim
19 words
The control unit of claim 76 including a storage element for storing the previous value of the command output.
Claim 82
Dependent Claim
38 words
The control unit of claim 76 wherein the control circuitry is adapted to be coupled to the two wire circuit and the command output is adapted to be transmitted on the two wire circuit for the remote device.
Claim 83
Dependent Claim
39 words
The control unit of claim 76 wherein the control circuitry is adapted to be coupled to a second two wire circuit and the command output is adapted to be transmitted on the second two-wire circuit for the remote device.
Claim 84
Dependent Claim
15 words
The control unit of claim 76 wherein the process variable sensor is in the housing.
Claim 85
Dependent Claim
19 words
The control unit of claim 76 wherein the command output comprises a digital signal in a carrier modulated format.
Claim 86
Dependent Claim
28 words
The control unit of claim 76 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 87
Dependent Claim
31 words
The control unit of claim 76 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 88
Dependent Claim
27 words
The control unit of claim 76 wherein the control circuitry is adapted to provide digital signal for the two wire circuit representative of a process control statistic.
Claim 89
Dependent Claim
29 words
The control unit of claim 76 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 90
Dependent Claim
29 words
The control unit of claim 76 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 91
Dependent Claim
26 words
The control unit of claim 76 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 92
Dependent Claim
32 words
The control unit of claim 76 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a specified limit.
Claim 93
Dependent Claim
34 words
The control unit of claim 76 wherein the input circuitry is further adapted to receive from the two wire circuit a coefficient of a term of an instruction set stored in the control unit.
Claim 94
Dependent Claim
25 words
The control unit of claim 76 wherein the sensed process variable relates to a flow and the command output is representative of a valve position.
Claim 95
Dependent Claim
71 words
The control unit of claim 76 wherein the command output, q k , is generally in accordance with the equation: ##EQU5## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 96
Dependent Claim
38 words
The control unit of claim 76 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 97
Dependent Claim
24 words
The control unit of claim 76 wherein the input circuitry receives a setpoint and the command output is further the function of the setpoint.
Claim 98
Dependent Claim
25 words
The control unit of claim 93 wherein the command output is further a function of a difference between the setpoint and the sensed process variable.
Claim 99
Dependent Claim
22 words
The control unit of claim 76 wherein the command output is further a function of a previous value of the command output.
Claim 100
Dependent Claim
14 words
The control unit of claim 95 wherein the function further comprises a PI function.
Claim 101
Dependent Claim
14 words
The control unit of claim 95 wherein the function further comprises a PD function.
Claim 102
Dependent Claim
14 words
The control unit of claim 95 wherein the function further comprises a PID function.
Claim 103
Dependent Claim
110 words
A smart field-mounted control unit for coupling to a two wire circuit, comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry receiving power from the two wire circuit for wholly powering the control unit and the input circuitry receiving a process signal from the two wire circuit representative of a process variable; and control circuitry in the housing operably coupled to the input circuitry, the control circuitry provides a command output to a remote device, the command output in a digital format which is a function of the process variable and a previous value of the command output.
Claim 104
Dependent Claim
110 words
A smart field-mounted control unit for coupling to a two wire circuit, comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry receiving power from the two wire circuit for wholly powering the control unit and the input circuitry receiving a process signal from the two wire circuit representative of a process variable; and control circuitry in the housing operably coupled to the input circuitry, the control circuitry provides a command output to a remote device, the command output in a digital format which is a function of the process variable and a previous value of the command output.
Claim 105
Dependent Claim
29 words
The control unit of claim 99 wherein the input circuitry is further adapted to receive an instruction from the two wire circuit to direct operation of the control unit.
Claim 106
Dependent Claim
34 words
The control unit of claim 99 wherein the input circuitry is further adapted to receive from the two wire circuit a coefficient of a term of an instruction set stored in the control unit.
Claim 107
Dependent Claim
28 words
The control unit of claim 99 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 108
Dependent Claim
29 words
The control unit of claim 99 wherein the control circuitry is adapted to provide a digital signal to the two wire circuit representative of a current mode of operation.
Claim 109
Dependent Claim
70 words
The control unit of claim 99 wherein the command output, q K , is generally in accordance with the equation: ##EQU6## where q K is the command output at the kth time, r i and y i are a setpoint and process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 110
Dependent Claim
14 words
The control unit of claim 99 wherein the function further comprises a PI function.
Claim 111
Dependent Claim
14 words
The control unit of claim 99 wherein the function further comprises a PD function.
Claim 112
Dependent Claim
14 words
The control unit of claim 99 wherein the function further comprises a PID function.
Claim 113
Dependent Claim
19 words
The control unit of claim 99 including a storage element for storing the previous value of the command output.
Claim 114
Dependent Claim
32 words
The control unit of claim 99 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 115
Dependent Claim
29 words
The control unit of claim 109 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 116
Dependent Claim
26 words
The control unit of claim 109 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 117
Dependent Claim
31 words
The control unit of claim 109 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the process variable exceeds a specified limit.
Claim 118
Dependent Claim
41 words
The control unit of claim 99 wherein the input circuitry is further adapted to receive a setpoint from the two wire circuit and the control circuitry adjusts the command output as a further function of the setpoint and the process variable.
Claim 119
Dependent Claim
24 words
The control unit of claim 113 wherein the command output is a further function of a difference between the setpoint and the process variable.
Claim 120
Dependent Claim
24 words
The control unit of claim 113 wherein the process variable is related to flow and the command output is representative of a valve position.
Claim 121
Dependent Claim
31 words
The control unit of claim 113 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 122
Dependent Claim
118 words
A smart field-mounted control unit for coupling to a two wire circuit for controlling a process control loop, comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry receiving power from the two wire circuit for wholly powering the control unit and the input circuitry adapted to receive a command and a process variable from the two wire circuit; and control circuitry in the housing operably coupled to the input circuitry and including at least one instruction set, wherein the control circuitry selects the instruction set in response to the command for providing a command output for a remote device as a function of the process variable.
Claim 123
Dependent Claim
118 words
A smart field-mounted control unit for coupling to a two wire circuit for controlling a process control loop, comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry receiving power from the two wire circuit for wholly powering the control unit and the input circuitry adapted to receive a command and a process variable from the two wire circuit; and control circuitry in the housing operably coupled to the input circuitry and including at least one instruction set, wherein the control circuitry selects the instruction set in response to the command for providing a command output for a remote device as a function of the process variable.
Claim 124
Dependent Claim
38 words
The control unit of claim 117 wherein the control circuitry is adapted to be coupled to the two wire circuit and the command output is adapted to be transmitted on the two wire circuit for the remote device.
Claim 125
Dependent Claim
39 words
The control unit of claim 117 wherein the control circuitry is adapted to be coupled to a second two wire circuit and the command output is adapted to be transmitted on the second two-wire circuit for the remote device.
Claim 126
Dependent Claim
19 words
The control unit of claim 117 wherein the command output comprises a digital signal in a carrier modulated format.
Claim 127
Dependent Claim
31 words
The control unit of claim 117 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 128
Dependent Claim
28 words
The control unit of claim 117 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 129
Dependent Claim
29 words
The control unit of claim 117 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 130
Dependent Claim
29 words
The control unit of claim 117 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 131
Dependent Claim
26 words
The control unit of claim 117 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 132
Dependent Claim
31 words
The control unit of claim 117 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the process variable exceeds a specified limit.
Claim 133
Dependent Claim
34 words
The control unit of claim 117 wherein the input circuitry is further adapted to receive from the two wire circuit a coefficient of a term of an instruction set stored in the control unit.
Claim 134
Dependent Claim
24 words
The control unit of claim 117 wherein the process variable is related to flow and the command output is representative of a valve position.
Claim 135
Dependent Claim
70 words
The control unit of claim 117 wherein the command output, q K , is generally in accordance with the equation: ##EQU7## where q K is the command output at the kth time, r i and y i are a setpoint and process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 136
Dependent Claim
14 words
The control unit of claim 117 wherein the function further comprises a PI function.
Claim 137
Dependent Claim
14 words
The control unit of claim 117 wherein the function further comprises a PD function.
Claim 138
Dependent Claim
14 words
The control unit of claim 117 wherein the function further comprises a PID function.
Claim 139
Dependent Claim
22 words
The control unit of claim 117 wherein the command output is further a function of a previous value of the command output.
Claim 140
Dependent Claim
19 words
The control unit of claim 133 including a storage element for storing the previous value of the command output.
Claim 141
Dependent Claim
25 words
The control unit of claim 117 wherein the input circuitry further receives a setpoint and the command output is further a function of the setpoint.
Claim 142
Dependent Claim
24 words
The control unit of claim 135 wherein the command output is further a function of a difference between the setpoint and the process variable.
Claim 143
Dependent Claim
150 words
A transmitter adapted for use in a conventional process control two wire circuit in which a parameter is represented by a 4-20 mA DC current in the two wire circuit and the transmitter is solely powered by such current, the transmitter comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit for receiving a first signal from the two wire circuit; a process sensor in the housing adapted to couple to a process and sense a process variable to produce a second signal which is representative of the process; and control circuitry in the housing coupled to the input circuitry and the process sensor, the control circuitry adapted to provide a command output for a remote device as a function of the first signal and the second signal, wherein the command output is representative of a control signal which is the parameter.
Claim 144
Dependent Claim
150 words
A transmitter adapted for use in a conventional process control two wire circuit in which a parameter is represented by a 4-20 mA DC current in the two wire circuit and the transmitter is solely powered by such current, the transmitter comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit for receiving a first signal from the two wire circuit; a process sensor in the housing adapted to couple to a process and sense a process variable to produce a second signal which is representative of the process; and control circuitry in the housing coupled to the input circuitry and the process sensor, the control circuitry adapted to provide a command output for a remote device as a function of the first signal and the second signal, wherein the command output is representative of a control signal which is the parameter.
Claim 145
Dependent Claim
28 words
A transmitter in accordance with claim 137 wherein the first signal is representative of a setpoint and the first signal is superimposed on the 4-20 mA DC current.
Claim 146
Dependent Claim
17 words
A transmitter in accordance with claim 137 wherein the command output is the 4-20 mA DC current.
Claim 147
Dependent Claim
16 words
A transmitter in accordance with claim 139 including a digital signal superimposed on the command output.
Claim 148
Dependent Claim
17 words
A transmitter in accordance with claim 140 wherein the digital signal is representative of the second signal.
Claim 149
Dependent Claim
187 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 150
Dependent Claim
187 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 151
Dependent Claim
15 words
The control unit of claim 142 wherein the command output comprises a 4-20 mA signal.
Claim 152
Dependent Claim
14 words
The control unit of claim 142 wherein the command output comprises a digital signal.
Claim 153
Dependent Claim
15 words
The control unit of claim 142 wherein the process variable sensor is in the housing.
Claim 154
Dependent Claim
29 words
The control unit of claim 142 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit representative of a redundant process variable.
Claim 155
Dependent Claim
27 words
The control unit of claim 142 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 156
Dependent Claim
27 words
The control unit of claim 142 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 157
Dependent Claim
28 words
The control unit of claim 142 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 158
Dependent Claim
36 words
The control unit of claim 142 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 159
Dependent Claim
29 words
The control unit of claim 142 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 160
Dependent Claim
26 words
The control unit of claim 142 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 161
Dependent Claim
31 words
The control unit of claim 142 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
Claim 162
Dependent Claim
34 words
The control unit of claim 142 wherein the input circuitry is further adapted to receive from the two wire circuit a coefficient of a term of an instruction set stored in the control unit.
Claim 163
Dependent Claim
25 words
The control unit of claim 142 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 164
Dependent Claim
31 words
The control unit of claim 142 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 165
Dependent Claim
28 words
The control unit of claim 142 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 166
Dependent Claim
29 words
The control unit of claim 142 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 167
Dependent Claim
71 words
The control unit of claim 142 wherein the command output, q K , is generally in accordance with the equation: ##EQU8## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 168
Dependent Claim
38 words
The control unit of claim 142 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 169
Dependent Claim
14 words
The control unit of claim 142 wherein the function further comprises a PI function.
Claim 170
Dependent Claim
14 words
The control unit of claim 142 wherein the function further comprises a PD function.
Claim 171
Dependent Claim
14 words
The control unit of claim 142 wherein the function further comprises a PID function.
Claim 172
Dependent Claim
19 words
The control unit of claim 142 wherein the command output is further a function of the sensed process variable.
Claim 173
Dependent Claim
25 words
The control unit of claim 164 wherein the command output is a further function of a difference between the setpoint and the sensed process variable.
Claim 174
Dependent Claim
189 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the input circuitry is further adapted to receive from the two wire circuit a coefficient of a term of an instruction set stored in the control unit.
Claim 175
Dependent Claim
189 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the input circuitry is further adapted to receive from the two wire circuit a coefficient of a term of an instruction set stored in the control unit.
Claim 176
Dependent Claim
15 words
The control unit of claim 166 wherein the command output comprises a 4-20 mA signal.
Claim 177
Dependent Claim
14 words
The control unit of claim 166 wherein the command output comprises a digital signal.
Claim 178
Dependent Claim
15 words
The control unit of claim 166 wherein the process variable sensor is in the housing.
Claim 179
Dependent Claim
29 words
The control unit of claim 166 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit representative of a redundant process variable.
Claim 180
Dependent Claim
27 words
The control unit of claim 166 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 181
Dependent Claim
27 words
The control unit of claim 166 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 182
Dependent Claim
28 words
The control unit of claim 166 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 183
Dependent Claim
36 words
The control unit of claim 166 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 184
Dependent Claim
25 words
The control unit of claim 166 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 185
Dependent Claim
31 words
The control unit of claim 166 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 186
Dependent Claim
28 words
The control unit of claim 166 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 187
Dependent Claim
29 words
The control unit of claim 166 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 188
Dependent Claim
71 words
The control unit of claim 166 wherein the command output, q K , is generally in accordance with the equation: ##EQU9## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 189
Dependent Claim
38 words
The control unit of claim 166 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 190
Dependent Claim
14 words
The control unit of claim 166 wherein the function further comprises a PI function.
Claim 191
Dependent Claim
14 words
The control unit of claim 166 wherein the function further comprises a PD function.
Claim 192
Dependent Claim
14 words
The control unit of claim 166 wherein the function further comprises a PID function.
Claim 193
Dependent Claim
19 words
The control unit of claim 166 wherein the command output is further a function of the sensed process variable.
Claim 194
Dependent Claim
25 words
The control unit of claim 169 wherein the command output is a further function of a difference between the setpoint and the sensed process variable.
Claim 195
Dependent Claim
32 words
The control unit of claim 166 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 196
Dependent Claim
29 words
The control unit of claim 186 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 197
Dependent Claim
26 words
The control unit of claim 186 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 198
Dependent Claim
31 words
The control unit of claim 186 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
Claim 199
Dependent Claim
186 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 200
Dependent Claim
186 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a serial number of the control unit.
Claim 201
Dependent Claim
15 words
The control unit of claim 190 wherein the command output comprises a 4-20 mA signal.
Claim 202
Dependent Claim
14 words
The control unit of claim 190 wherein the command output comprises a digital signal.
Claim 203
Dependent Claim
15 words
The control unit of claim 190 wherein the process variable sensor is in the housing.
Claim 204
Dependent Claim
29 words
The control unit of claim 190 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit representative of a redundant process variable.
Claim 205
Dependent Claim
27 words
The control unit of claim 190 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 206
Dependent Claim
27 words
The control unit of claim 190 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 207
Dependent Claim
28 words
The control unit of claim 190 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 208
Dependent Claim
36 words
The control unit of claim 190 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 209
Dependent Claim
28 words
The control unit of claim 190 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 210
Dependent Claim
29 words
The control unit of claim 190 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 211
Dependent Claim
71 words
The control unit of claim 190 wherein the command output, q K , is generally in accordance with the equation: ##EQU10## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 212
Dependent Claim
38 words
The control unit of claim 190 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 213
Dependent Claim
14 words
The control unit of claim 190 wherein the function further comprises a PI function.
Claim 214
Dependent Claim
14 words
The control unit of claim 190 wherein the function further comprises a PD function.
Claim 215
Dependent Claim
14 words
The control unit of claim 190 wherein the function further comprises a PID function.
Claim 216
Dependent Claim
25 words
The control unit of claim 190 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 217
Dependent Claim
19 words
The control unit of claim 190 wherein the command output is further a function of the sensed process variable.
Claim 218
Dependent Claim
25 words
The control unit of claim 207 wherein the command output is a further function of a difference between the setpoint and the sensed process variable.
Claim 219
Dependent Claim
32 words
The control unit of claim 190 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 220
Dependent Claim
29 words
The control unit of claim 209 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 221
Dependent Claim
26 words
The control unit of claim 209 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 222
Dependent Claim
31 words
The control unit of claim 209 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
Claim 223
Dependent Claim
169 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the function further comprises a PI function.
Claim 224
Dependent Claim
169 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the function further comprises a PI function.
Claim 225
Dependent Claim
15 words
The control unit of claim 213 wherein the command output comprises a 4-20 mA signal.
Claim 226
Dependent Claim
14 words
The control unit of claim 213 wherein the command output comprises a digital signal.
Claim 227
Dependent Claim
15 words
The control unit of claim 213 wherein the process variable sensor is in the housing.
Claim 228
Dependent Claim
29 words
The control unit of claim 213 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit representative of a redundant process variable.
Claim 229
Dependent Claim
27 words
The control unit of claim 213 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 230
Dependent Claim
27 words
The control unit of claim 213 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 231
Dependent Claim
28 words
The control unit of claim 213 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 232
Dependent Claim
36 words
The control unit of claim 213 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 233
Dependent Claim
25 words
The control unit of claim 213 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 234
Dependent Claim
28 words
The control unit of claim 213 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 235
Dependent Claim
29 words
The control unit of claim 213 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 236
Dependent Claim
71 words
The control unit of claim 213 wherein the command output, q K , is generally in accordance with the equation: ##EQU11## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 237
Dependent Claim
38 words
The control unit of claim 213 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 238
Dependent Claim
19 words
The control unit of claim 213 wherein the command output is further a function of the sensed process variable.
Claim 239
Dependent Claim
25 words
The control unit of claim 227 wherein the command output is a further function of a difference between the setpoint and the sensed process variable.
Claim 240
Dependent Claim
32 words
The control unit of claim 213 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 241
Dependent Claim
29 words
The control unit of claim 229 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 242
Dependent Claim
26 words
The control unit of claim 229 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 243
Dependent Claim
31 words
The control unit of claim 229 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
Claim 244
Dependent Claim
169 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the function further comprises a PD function.
Claim 245
Dependent Claim
169 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the function further comprises a PD function.
Claim 246
Dependent Claim
15 words
The control unit of claim 233 wherein the command output comprises a 4-20 mA signal.
Claim 247
Dependent Claim
14 words
The control unit of claim 233 wherein the command output comprises a digital signal.
Claim 248
Dependent Claim
15 words
The control unit of claim 233 wherein the process variable sensor is in the housing.
Claim 249
Dependent Claim
29 words
The control unit of claim 233 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit representative of a redundant process variable.
Claim 250
Dependent Claim
27 words
The control unit of claim 233 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 251
Dependent Claim
27 words
The control unit of claim 233 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 252
Dependent Claim
28 words
The control unit of claim 233 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 253
Dependent Claim
36 words
The control unit of claim 233 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 254
Dependent Claim
25 words
The control unit of claim 233 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 255
Dependent Claim
28 words
The control unit of claim 233 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 256
Dependent Claim
29 words
The control unit of claim 233 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 257
Dependent Claim
71 words
The control unit of claim 233 wherein the command output, q K , is generally in accordance with the equation: ##EQU12## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 258
Dependent Claim
38 words
The control unit of claim 233 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 259
Dependent Claim
19 words
The control unit of claim 233 wherein the command output is further a function of the sensed process variable.
Claim 260
Dependent Claim
25 words
The control unit of claim 247 wherein the command output is a further function of a difference between the setpoint and the sensed process variable.
Claim 261
Dependent Claim
32 words
The control unit of claim 233 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 262
Dependent Claim
29 words
The control unit of claim 249 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 263
Dependent Claim
26 words
The control unit of claim 249 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 264
Dependent Claim
31 words
The control unit of claim 249 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
Claim 265
Dependent Claim
169 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the function further comprises a PID function.
Claim 266
Dependent Claim
169 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; and wherein the function further comprises a PID function.
Claim 267
Dependent Claim
15 words
The control unit of claim 253 wherein the command output comprises a 4-20 mA signal.
Claim 268
Dependent Claim
14 words
The control unit of claim 253 wherein the command output comprises a digital signal.
Claim 269
Dependent Claim
15 words
The control unit of claim 253 wherein the process variable sensor is in the housing.
Claim 270
Dependent Claim
29 words
The control unit of claim 253 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit representative of a redundant process variable.
Claim 271
Dependent Claim
27 words
The control unit of claim 253 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 272
Dependent Claim
27 words
The control unit of claim 253 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 273
Dependent Claim
28 words
The control unit of claim 253 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 274
Dependent Claim
36 words
The control unit of claim 253 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 275
Dependent Claim
25 words
The control unit of claim 253 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 276
Dependent Claim
28 words
The control unit of claim 253 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 277
Dependent Claim
29 words
The control unit of claim 253 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 278
Dependent Claim
71 words
The control unit of claim 253 wherein the command output, q K , is generally in accordance with the equation: ##EQU13## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 279
Dependent Claim
38 words
The control unit of claim 253 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 280
Dependent Claim
19 words
The control unit of claim 253 wherein the command output is further a function of the sensed process variable.
Claim 281
Dependent Claim
25 words
The control unit of claim 267 wherein the command output is a further function of a difference between the setpoint and the sensed process variable.
Claim 282
Dependent Claim
32 words
The control unit of claim 253 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 283
Dependent Claim
29 words
The control unit of claim 269 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 284
Dependent Claim
26 words
The control unit of claim 269 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 285
Dependent Claim
31 words
The control unit of claim 269 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
Claim 286
Dependent Claim
179 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; wherein the command output is further a function of a difference between the setpoint and the sensed process variable.
Claim 287
Dependent Claim
179 words
A smart field-mounted control unit for coupling to a two wire DC current process control circuit which carries a loop current, the two wire circuit electrically connected in series with a power source, a remote device and the control unit, the control unit comprising: a housing; input circuitry in the housing adapted to be operably coupled to the two wire circuit, the input circuitry adapted to receive power from the power source through the two wire circuit which wholly powers the control unit and adapted to receive a setpoint from the two wire circuit; a process variable sensor which provides a sensed process variable; control circuitry in the housing operably coupled to the input circuitry, the process variable sensor, and the two wire circuit whereby the control unit is adapted to be electrically connected in series with the two wire circuit and the control circuitry provides a command output for the two wire circuit as a function of the setpoint; wherein the command output is further a function of a difference between the setpoint and the sensed process variable.
Claim 288
Dependent Claim
15 words
The control unit of claim 273 wherein the command output comprises a 4-20 mA signal.
Claim 289
Dependent Claim
14 words
The control unit of claim 273 wherein the command output comprises a digital signal.
Claim 290
Dependent Claim
15 words
The control unit of claim 273 wherein the process variable sensor is in the housing.
Claim 291
Dependent Claim
29 words
The control unit of claim 273 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit representative of a redundant process variable.
Claim 292
Dependent Claim
27 words
The control unit of claim 273 wherein the control circuitry is adapted to concurrently provide the command output and a digital signal for the two wire circuit.
Claim 293
Dependent Claim
27 words
The control unit of claim 273 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit in a carrier modulated format.
Claim 294
Dependent Claim
28 words
The control unit of claim 273 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of the sensed process variable.
Claim 295
Dependent Claim
36 words
The control unit of claim 273 wherein the input circuitry is further adapted to receive a process signal from the two wire circuit which is representative of an instruction to direct operation of the control unit.
Claim 296
Dependent Claim
25 words
The control unit of claim 273 wherein the sensed process variable is related to flow and the command output is representative of a valve position.
Claim 297
Dependent Claim
28 words
The control unit of claim 273 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a process control statistic.
Claim 298
Dependent Claim
29 words
The control unit of claim 273 wherein the control circuitry is adapted to provide a digital signal for the two wire circuit representative of a current mode of operation.
Claim 299
Dependent Claim
71 words
The control unit of claim 273 wherein the command output, q K , is generally in accordance with the equation: ##EQU14## where q K is the command output at the kth time, r i and y i are a setpoint and sensed process variable values at an ith time respectively, i varies from 0 to k and a i and b i are application specific constants which may be time varying.
Claim 300
Dependent Claim
38 words
The control unit of claim 273 including scaling circuitry coupled to the process variable sensor which scales the sensed process variable and provides a scaled process variable to the control circuitry for use in providing the command output.
Claim 301
Dependent Claim
14 words
The control unit of claim 273 wherein the function further comprises a PI function.
Claim 302
Dependent Claim
14 words
The control unit of claim 273 wherein the function further comprises a PD function.
Claim 303
Dependent Claim
14 words
The control unit of claim 273 wherein the function further comprises a PID function.
Claim 304
Dependent Claim
32 words
The control unit of claim 273 wherein the input circuitry is further adapted to receive a command from the two wire circuit which selects an instruction set stored in the control unit.
Claim 305
Dependent Claim
29 words
The control unit of claim 290 wherein the command comprises a shut down command which selects an instruction set for the control circuitry for safely shutting down a process.
Claim 306
Dependent Claim
26 words
The control unit of claim 290 wherein the command instructs the control unit to adaptively set its own instruction set for operation of the control circuitry.
Claim 307
Dependent Claim
31 words
The control unit of claim 290 wherein the command instructs the control unit to enter an exceptional mode and transmit a digital signal if the sensed process variable exceeds a limit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-10-19 | 2002-04-20 | 2002-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-10-19 | 2006-04-20 | 2006-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-10-19 | 2010-04-20 | 2010-10-20 | $7700.00 | Window Closed / Lapsed |