Automated remote telemetry paging system

Claim 2

In an automated telemetry paging system for providing remote pager notification of deviations in selected operating parameters measured at a specific site location wherein indication of each of the selected parameters and the unacceptable deviation therefrom is provided in the form of a plurality of electrical status signals each representative of one of the selected parameters, telephone company line connections to telephone central switching equipment for dialing selected telephone numbers is provided at the site location, and pager network communications equipment is provided that is in communication with the telephone central switching equipment and in communication with a plurality of paging devices, a remote telemetry unit located at the site location comprising a programmed microprocessor including data input/output means, memory means, a central processing unit (CPU), and a real time clock, status signal receiving means for receiving and isolating the received electrical status signals, said receiving means isolating said received signals for eliminating short duty-cycle over-voltage signals and shaping said received signals into digital signals representative of said received status signals, said digital signals applied as inputs to said input/output means, interrogation means controlled by said CPU and cooperating with said real time clock for continuously scanning said digital status signals applied to said input/output means at a predetermined rate, discrimination means controlled by said CPU for reading and comparing said digital status signals applied to said input/output means against a current status signal reference stored in said memory means and in response to detecting a deviation therefrom initiating a time delay prior to again reading and comparing said digital status signals against said current status signal reference, and if said second comparison after said time delay detects a deviation from said reference signalling said CPU of the presence of a valid status signal indicating an unacceptable parameter deviation, formatting means controlled by said CPU for reading said digital status signals, correlating said digital signals with a message table preprogrammed into said memory means and converting said digital status signals appearing at said input/output means into a digital status message of a preselected format that is representative of the identification of the specific site location and successive codes indicating the parameters that have reached an unacceptable deviation, digital to multiple frequency (DTMF) conversion means for converting said digital status message generated by said formatting means to audio frequency signals for transmission over the telephone lines to said paging network equipment, and telephone interface means for interfacing between said DTMF conversion means and the telephone company line interconnected to the telephone central switching equipment for applying audio frequency telephone signals to the telephone lines for application to said telephone central switching equipment and the pager network equipment, wherein said CPU in response to said formatted digital status message reads digital signals stored in said memory means representative of a preselected number of pager telephone numbers and applies said digital signals in serial order to said DTMF conversion means for converting said signals representative of said pager telephone numbers to audio frequency signals for application through said telephone interface means and the telephone central switching equipment directly to the paging network equipment for automatically and sequentially dialing said preselected pager telephone numbers, and wherein said CPU further applies said digital status message in serial order to said DTMF conversion means for converting said digital signals to audio frequency signals for transmission over the telephone lines to the pager network equipment for broadcast to the paging devices for alphanumeric display and said digital status message therein in said preselected message format.

Claim 3

The remote telemetry unit as described in claim 1, wherein said CPU applies said digital status message signals to said DTMF conversion means only after receiving audio tone signals from the pager network equipment that the complete pager telephone number has been dialed and the pager is accessed.

Claim 4

The remote telemetry unit as described in claim 1, wherein said CPU automatically dials each of said preselected pager telephone numbers a predetermined number of times.

Claim 5

The remote telemetry unit as described in claim 1, wherein said memory means may be programmed to receive data representative of the selected deviation parameters for temporarily masking preselected ones of said deviation parameters during interrogation by said interrogation means.

Claim 6

The remote telemetry unit as described in claim 1, wherein said formatting means formats both single digit and multiple digit status codes for use in establishing said digital status message.

Claim 7

The remote telemetry unit as described in claim 1, wherein said current status signal reference is the last such status determined for each parameter and reported in a digital status message to said pagers and then stored in said memory means.

Claim 8

The remote telemetry unit as described in claim 1, wherein said status signal receiving means includes an optical coupling circuit means responsive to said received input status signals for optically isolating and limiting any spurious electrical spikes and over-voltage signals present in said received input status signals.

Claim 9

The remote telemetry unit as described in claim 7, wherein said status signal receiving means further includes an isolated source of electrical power for said optical coupling circuit means, and wherein said optical coupling circuit means acts as the load for said isolated power supply for causing said spurious electrical spikes and over-voltage signals to be routed to said isolated source of electrical power for absorbing such short-duty cycle over-voltage signals.

Claim 10

The remote telemetry means as described in claim 1, wherein said DTMF conversion means comprises a DTMF transceiver circuit.

Claim 11

The remote telemetry unit as described in claim 1, wherein said telephone interface means includes relay controlled hook-switch contacts for selectively interconnecting said DTMF conversion means audio frequency output signals to the telephone lines, said relay operable in response to an electrical control signal received from said CPU.

Claim 12

The remote telemetry unit as described in claim 1, wherein said time delay introduced by said discrimination means after the detection of a deviate status signal is preselected based on the characteristics of the means providing said electrical signals indicative of the measured parameter as well as the characteristics of the selected operating parameters and is a substantially long time period as compared to successive clock pulses.

Claim 13

The remote telemetry unit as described in claim 1, wherein the electrical status signals representative of the selected parameters and unacceptable deviation therefrom are provided by dry-contact switch closures the opening and closing thereof being indicative of said selected parameter and the unacceptable deviation therefrom.

Claim 14

In a telemetry paging system for providing remote pager notification of deviations in selected operating parameters measured at a specific site location wherein indication of each of the selected parameters and the unacceptable deviation therefrom is provided in the form of a plurality of electrical status signal each representative of one of the selected parameters, telephone company line connections to telephone central switching equipment for dialing selected telephone numbers is provided at the site location, and pager network communications equipment is provided that is in communication with the telephone central switching equipment and in communication with a plurality of paging devices, the improvement comprising telemetry means located at said site location and receiving said electrical status signals indicative of each of the selected parameters and any unacceptable deviation therefrom and in response thereto generating a status message identifying the remote site location and codes for indicating the deviated parameters and generating telephone audio tone messages representative of the status message for communicating with telephone computer switching and paging equipment, wherein said telemetry means comprises, status signal receiving means for receiving and isolating the signals received from said status means, said status signal receiving means isolating said signals for protecting said telemetry means from any spurious electrical spikes and over-voltage signal inputs, a programmed microprocessor (MPU) including a programmable expanded memory means, and digital to multiple frequency (DTMF) conversion means for converting digital status message signals generated by said MPU to audio frequency signals for transmission over the telephone lines, and telephone interface means for interfacing between said digital to multiple frequency conversion means and the telephone company line interconnected to the telephone office switching equipment in response to control signals from said MPU for interconnecting audio frequency telephone signals to the telephone lines for application to said telephone company switching equipment and the pager network equipment, wherein said MPU interrogates said received electrical status signals at a predetermined rate functionally related to the MPU clock rate and in response to the occurrence of a deviate status signal introducing a predetermined time delay before further interrogating said status signals for comparison with a previously determined status reference maintained in said MPU memory for determining whether said deviate status signal is an unacceptable parametric deviation, wherein said MPU in response to determining that an unacceptable status signal deviation has occurred generates a digital status message identifying the remote site location and the selected parametric deviation, and wherein said MPU energizes said telephone interface means when said digital stats message is completed and dials preselected pager telephone numbers stored in said expanded programmable memory means through the telephone central switching equipment and pager network equipment, and wherein said MPU further applies digital signals representative of said digital status message to said DTMF conversion means for converting said digital signals to audio frequency signals for transmission over the telephone lines to the pager network equipment for broadcast to the pager devices for displaying said digital status message therein.

Claim 15

In a telemetry paging system for providing remote pager notification of deviations in selected operating parameters measured at a specific site location wherein indication of each of the selected parameters and the unacceptable deviation therefrom is provided in the form of a plurality of electrical status signal each representative of one of the selected parameters, telephone company line connections to telephone central switching equipment for dialing selected telephone numbers is provided at the site location, and pager network communications equipment is provided that is in communication with the telephone central switching equipment and in communication with a plurality of paging devices, the improvement comprising telemetry means located at said site location and receiving said electrical status signals indicative of each of the selected parameters and any unacceptable deviation therefrom and in response thereto generating a status message identifying the remote site location and codes for indicating the deviated parameters and generating telephone audio tone messages representative of the status message for communicating with telephone computer switching and paging equipment, wherein said telemetry means comprises, status signal receiving means for receiving and isolating the signals received from said status means, said status signal receiving means isolating said signals for protecting said telemetry means from any spurious electrical spikes and over-voltage signal inputs, a programmed microprocessor (MPU) including a programmable expanded memory means, and digital to multiple frequency (DTMF) conversion means for converting digital status message signals generated by said MPU to audio frequency signals for transmission over the telephone lines, and telephone interface means for interfacing between said digital to multiple frequency conversion means and the telephone company line interconnected to the telephone office switching equipment in response to control signals from said MPU for interconnecting audio frequency telephone signals to the telephone lines for application to said telephone company switching equipment and the pager network equipment, wherein said MPU interrogates said received electrical status signals at a predetermined rate functionally related to the MPU clock rate and in response to the occurrence of a deviate status signal introducing a predetermined time delay before further interrogating said status signals for comparison with a previously determined status reference maintained in said MPU memory for determining whether said deviate status signal is an unacceptable parametric deviation, wherein said MPU in response to determining that an unacceptable status signal deviation has occurred generates a digital status message identifying the remote site location and the selected parametric deviation, and wherein said MPU energizes said telephone interface means when said digital stats message is completed and dials preselected pager telephone numbers stored in said expanded programmable memory means through the telephone central switching equipment and pager network equipment, and wherein said MPU further applies digital signals representative of said digital status message to said DTMF conversion means for converting said digital signals to audio frequency signals for transmission over the telephone lines to the pager network equipment for broadcast to the pager devices for displaying said digital status message therein.

Claim 16

The remote telemetry means as described in claim 13, wherein said MPU further automatically and sequentially dials said preselected number of remote pager telephone numbers stored in said expanded programmable memory means by applying digital signals representative of said telephone numbers to said DTMF conversion means for converting said digital signals to telephone audio tone dialing signals.

Claim 17

The remote telemetry means as described in claim 13, wherein said MPU applies said digital signals representative of said digital status message to said DTMF conversion means only after receiving audio tone signals from the pager network equipment that the complete pager telephone number has been dialed and the pager is accessed.

Claim 18

The remote telemetry means as described in claim 13, wherein said MPU automatically dials each of said preselected pager telephone numbers a preselected number of times.

Claim 19

The remote telemetry means as described in claim 13, wherein data representative of selected deviation parameters that are to be temporarily ignored at the site location is programmed into the MPU programmable memory for masking said selected deviation parameters during the MPU interrogation of said input electrical status signals.

Claim 20

The remote telemetry means as described in claim 13, wherein said MPU formats both single digit and multiple digit status codes for use in building said digital status message.

Claim 21

The remote telemetry means as described in claim 13, wherein said previously determined status reference is the last such status determined for each parameter and reported in a status message to said pagers and then stored in digital form in said MPU.

Claim 22

The remote telemetry means as described in claim 13, wherein said status signal receiving means includes an optical coupling circuit means responsive to said received input status signals for optically isolating and limiting any spurious electrical spikes and over-voltage signals present in said received input status signals.

Claim 23

The remote telemetry means as described in claim 20, wherein said status signal receiving means further includes an isolated source of electrical power for said optical coupling circuit means, and wherein said optical coupling circuit means acts as the load for said isolated power supply for causing said spurious electrical spikes and over-voltage signals to be routed to said isolated source of electrical power for absorbing such short-duty cycle over-voltage signals.

Claim 24

The remote telemetry means as described in claim 13, wherein said DTMF conversion means comprises a DTMF transceiver circuit.

Claim 25

The remote telemetry unit as described in claim 13, wherein said telephone interface means includes relay controlled hook-switch contacts for selectively interconnecting said DTMF conversion means audio frequency output signals to the telephone lines, said relay operable in response to an electrical control signal received from said MPU.

Claim 26

The remote telemetry unit as described in claim 13, wherein said time delay introduced by said discrimination means after the detection of a deviate status signal is preselected based on the characteristics of the means providing said electrical signals indicative of the measured parameter as well as the characteristics of the selected operating parameters and is a substantially long time period as compared to successive clock pulses.

Claim 27

The remote telemetry unit as described in claim 13, wherein the electrical status signals representative of the selected parameters and unacceptable deviation therefrom are provided by dry-contact switch closures the opening and closing thereof being indicative of said selected parameter and the unacceptable deviation therefrom.

Claim 28

In an automated telemetry system for providing remote notification of deviations in selected operating parameters measured at a specific site location wherein indication of each of the selected parameters and the unacceptable deviation therefrom is provided in the form of a plurality of electrical status signals each representative of one of the selected parameters, telephone company line connections to telephone control switching equipment for dialing selected telephone numbers is provided at the site location, and communications equipment is provided that is in communication with the telephone central switching equipment for providing remote notification of the parameter deviations on a real time basis, a remote telemetry unit (RTU) located at the site location comprising a programmed microprocessor including data input/output means, memory means, a central processing unit (CPU), and a real time clock, dry-contact switch closures the opening and closure thereof being indicative of said selected operating parameters and the unacceptable deviation therefrom for generating electrical status signals representative thereof, status signal receiving means for receiving and isolating the received electrical status signals, said receiving means including optical coupling circuit means responsive to said received input status signals for optically isolating and limiting any spurious electrical spikes and short duty-cycle over-voltage signals present in said received input status signals, said receiving means shaping said received signals into digital signals representative of said received status signals and applying said digital signals as inputs to said data input/output means, said status signal receiving means further including an isolated source of electrical power for said optical coupling circuit means and wherein said optical coupling circuit means acts as the load for said isolated power supply for causing said spurious electrical spikes and over-voltage signals to be routed to said isolated source of electrical power for absorbing such short-duty cycle over-voltage signals, interrogation means controlled by said CPU and cooperating with said real time clock for continuously scanning said digital status signals applied to said data input/output means at a predetermined rate, wherein data representative of selected deviation parameters that are to be temporarily ignored at the site location is programmed to said RTU memory means for masking said selected deviation parameters during interrogation by said interrogation means, discrimination means controlled by said CPU for reading and comparing said digital status signals applied to said input/output means against a current status signal reference stored in said memory means and in response to detecting a deviation therefrom initiating a time delay prior to again reading and comparing said digital status signals against said current status signal reference, and if said second comparison after said time delay detects a deviation from said reference, signaling said CPU of the presence of a valid status signal indicating an unacceptable parameter deviation, wherein said time delay is preselected based on the characteristics of the dry-contact switch closure providing said electrical signals indicative of the selected measured parameters as well as the characteristics of the operating parameters and is a substantially long time period as compared to successive clock pulses. formatting means controlled by said CPU for reading said digital status signals, correlating said digital signals with a message table preprogrammed into said memory means and converting said digital status signals appearing at said input/output means into a digital status message of a preselected format that is representative of the identification of the specific location and successive codes indicating the parameters that have reached an unacceptable deviation, said formatting means formatting both single digital and multiple status codes for use in establishing said digital status message, digital to multiple frequency conversion means for converting said digital status message generated by said formatting means to audio frequency signals for transmission over the telephone lines to said communications equipment, and telephone interface means for interfacing between said DTMF conversion means and the telephone company line interconnected to the telephone central switching equipment and including relay controlled hook-switch contacts for selectively interconnecting said DTMF conversion means audio frequency output signals to said telephone lines for application to said telephone central switching equipment and the communications equipment, said relay operable in response to an electrical control signal received from said CFU, wherein said CPU in response to said formatted digital status message reads digital signals stored in said memory means representative of preselected telephone numbers and applies said digital signals in serial order to said DTMF conversion means for converting said signals representative of said telephone numbers to audio frequency signals for application through said telephone interface means and the telephone central switching equipment for automatically and sequentially dialing said telephone numbers for reaching said communications equipment, and wherein said CPU further applies said digital status message in serial order to said DTMF conversion means for converting said digital signals to audio frequency signals for transmission over the telephone lines to the communications equipment for alphanumeric display of said digital status message therein in said preselected message format.

Claim 29

In an automated telemetry system for providing remote notification of deviations in selected operating parameters measured at a specific site location wherein indication of each of the selected parameters and the unacceptable deviation therefrom is provided in the form of a plurality of electrical status signals each representative of one of the selected parameters, telephone company line connections to telephone control switching equipment for dialing selected telephone numbers is provided at the site location, and communications equipment is provided that is in communication with the telephone central switching equipment for providing remote notification of the parameter deviations on a real time basis, a remote telemetry unit (RTU) located at the site location comprising a programmed microprocessor including data input/output means, memory means, a central processing unit (CPU), and a real time clock, dry-contact switch closures the opening and closure thereof being indicative of said selected operating parameters and the unacceptable deviation therefrom for generating electrical status signals representative thereof, status signal receiving means for receiving and isolating the received electrical status signals, said receiving means including optical coupling circuit means responsive to said received input status signals for optically isolating and limiting any spurious electrical spikes and short duty-cycle over-voltage signals present in said received input status signals, said receiving means shaping said received signals into digital signals representative of said received status signals and applying said digital signals as inputs to said data input/output means, said status signal receiving means further including an isolated source of electrical power for said optical coupling circuit means and wherein said optical coupling circuit means acts as the load for said isolated power supply for causing said spurious electrical spikes and over-voltage signals to be routed to said isolated source of electrical power for absorbing such short-duty cycle over-voltage signals, interrogation means controlled by said CPU and cooperating with said real time clock for continuously scanning said digital status signals applied to said data input/output means at a predetermined rate, wherein data representative of selected deviation parameters that are to be temporarily ignored at the site location is programmed to said RTU memory means for masking said selected deviation parameters during interrogation by said interrogation means, discrimination means controlled by said CPU for reading and comparing said digital status signals applied to said input/output means against a current status signal reference stored in said memory means and in response to detecting a deviation therefrom initiating a time delay prior to again reading and comparing said digital status signals against said current status signal reference, and if said second comparison after said time delay detects a deviation from said reference, signaling said CPU of the presence of a valid status signal indicating an unacceptable parameter deviation, wherein said time delay is preselected based on the characteristics of the dry-contact switch closure providing said electrical signals indicative of the selected measured parameters as well as the characteristics of the operating parameters and is a substantially long time period as compared to successive clock pulses. formatting means controlled by said CPU for reading said digital status signals, correlating said digital signals with a message table preprogrammed into said memory means and converting said digital status signals appearing at said input/output means into a digital status message of a preselected format that is representative of the identification of the specific location and successive codes indicating the parameters that have reached an unacceptable deviation, said formatting means formatting both single digital and multiple status codes for use in establishing said digital status message, digital to multiple frequency conversion means for converting said digital status message generated by said formatting means to audio frequency signals for transmission over the telephone lines to said communications equipment, and telephone interface means for interfacing between said DTMF conversion means and the telephone company line interconnected to the telephone central switching equipment and including relay controlled hook-switch contacts for selectively interconnecting said DTMF conversion means audio frequency output signals to said telephone lines for application to said telephone central switching equipment and the communications equipment, said relay operable in response to an electrical control signal received from said CFU, wherein said CPU in response to said formatted digital status message reads digital signals stored in said memory means representative of preselected telephone numbers and applies said digital signals in serial order to said DTMF conversion means for converting said signals representative of said telephone numbers to audio frequency signals for application through said telephone interface means and the telephone central switching equipment for automatically and sequentially dialing said telephone numbers for reaching said communications equipment, and wherein said CPU further applies said digital status message in serial order to said DTMF conversion means for converting said digital signals to audio frequency signals for transmission over the telephone lines to the communications equipment for alphanumeric display of said digital status message therein in said preselected message format.

Claim 30

The remote telemetry system as described in claim 26, wherein said current status signal reference is the last such status determined for each parameter and reported in a digital status message to said communications equipment and then stored in said memory means.

Claim 31

The remote telemetry system as described in claim 26, wherein said DTMF conversion means comprises a DTMF transceiver circuit.

Claim 32

A telemetry unit for providing notification to remote pager network communications equipment of changes in selected operating parameters measured at a specified site location wherein each of the selected parameters and the changes therein are provided in the form of electrical status signals representative thereof, including a telephone line interconnected to telephone central switching equipment and interposed between said telemetry unit and the remote communications equipment, comprising a programmed microprocessor, including data input/output means, memory means, a central processing unit (CPU), and a real time clock, status signal receiving and isolating the received electrical status signals, said receiving means including an optical coupling circuit means responsive to said received input status signal for optically isolating and limiting any spurious electrical spikes and short duty-cycle over-voltage signals present in said received input status signals, said receiving means shaping said received signals into digital signals representative of said received status signals and applying said digital signals as inputs to said input/output means, said status signal receiving means further including an isolated source of electrical power for said optical coupling circuit means and wherein said optical coupling circuit means acts as the load for said isolated power supply for causing said spurious electrical spikes and over-voltage signals to be routed to said isolated source of electrical power for absorbing such short-duty cycle over-voltage signals, interrogation means controlled by said CPU and cooperating with said real time clock for continuously scanning said digital status signals applied to said input/output means at a predetermined rate, wherein data representative of selected deviation parameters that are to be temporarily ignored at the site location is programmed into said memory means for masking said selected deviation parameters during interrogation by said interrogation means, discrimination means controlled by said CPU for reading and comparing said digital status signals applied to said input/output means against a current status signal reference stored in said memory means and in response detecting a deviation therefrom initiating a time delay prior to again reading and comparing said digital status signals against said current status signal reference, and if said second comparison after said time delay detects a deviation from said reference, signaling said CPU of the presence of a valid status signal indicating an unacceptable parameter deviation, wherein said time delay is preselected based on the characteristics of the means providing said electrical signals indicative of the selected measured parameters as well as the characteristics of the operating parameters and is a substantially long time period as compared to successive clock pulses, formatting means controlled by said CPU for reading said digital status signals, correcting said digital signals with a message table preprogrammed into said memory means and converting said digital status signals appearing at said input/output means into digital status message of a preselected format that is representative of the identification of the specific location and successive codes indicating the parameters that have reached an unacceptable deviation, said formatting means formatting both single digit and multiple digit status codes for use in establishing said digital status message, digital to multiple frequency (DTMF) conversion means for converting said digital status message generated by said formatting means to audio frequency signals for transmission over the telephone line to said remote communications equipment, and telephone interface means for interfacing between said DTMF conversion means and the telephone company line interconnected to the telephone central switching equipment and including relay controlled hook-switch contacts for selectively interconnecting said DTMF conversion means audio frequency output signals to said telephone line for application to the remote pager network communications equipment, said relay operable in response to an electrical control signal received from said CPU, wherein said CPU in response to said formatted digital status message reads digital signals stored in said memory means representative of a preselected number of pager telephone numbers and applies said digital signals in serial order to said DTMF conversion means for converting said signals representative of said pager telephone numbers to audio frequency signals for application through said telephone interface means and the telephone central switching equipment directly to the pager network communications equipment for automatically and sequentially dialing said preselected pager telephone numbers, and wherein said CPU further applies said digital status message in serial order to said DTMF conversion means for converting said digital signals to audio frequency signals for transmission over the telephone lines to the pager network communications equipment for broadcast to the paging devices for alphanumeric display of said digital status message therein in said preselected message format, and wherein said CPU automatically dials each of said pager telephone numbers a preselected number of times.

Claim 33

A telemetry unit for providing notification to remote pager network communications equipment of changes in selected operating parameters measured at a specified site location wherein each of the selected parameters and the changes therein are provided in the form of electrical status signals representative thereof, including a telephone line interconnected to telephone central switching equipment and interposed between said telemetry unit and the remote communications equipment, comprising a programmed microprocessor, including data input/output means, memory means, a central processing unit (CPU), and a real time clock, status signal receiving and isolating the received electrical status signals, said receiving means including an optical coupling circuit means responsive to said received input status signal for optically isolating and limiting any spurious electrical spikes and short duty-cycle over-voltage signals present in said received input status signals, said receiving means shaping said received signals into digital signals representative of said received status signals and applying said digital signals as inputs to said input/output means, said status signal receiving means further including an isolated source of electrical power for said optical coupling circuit means and wherein said optical coupling circuit means acts as the load for said isolated power supply for causing said spurious electrical spikes and over-voltage signals to be routed to said isolated source of electrical power for absorbing such short-duty cycle over-voltage signals, interrogation means controlled by said CPU and cooperating with said real time clock for continuously scanning said digital status signals applied to said input/output means at a predetermined rate, wherein data representative of selected deviation parameters that are to be temporarily ignored at the site location is programmed into said memory means for masking said selected deviation parameters during interrogation by said interrogation means, discrimination means controlled by said CPU for reading and comparing said digital status signals applied to said input/output means against a current status signal reference stored in said memory means and in response detecting a deviation therefrom initiating a time delay prior to again reading and comparing said digital status signals against said current status signal reference, and if said second comparison after said time delay detects a deviation from said reference, signaling said CPU of the presence of a valid status signal indicating an unacceptable parameter deviation, wherein said time delay is preselected based on the characteristics of the means providing said electrical signals indicative of the selected measured parameters as well as the characteristics of the operating parameters and is a substantially long time period as compared to successive clock pulses, formatting means controlled by said CPU for reading said digital status signals, correcting said digital signals with a message table preprogrammed into said memory means and converting said digital status signals appearing at said input/output means into digital status message of a preselected format that is representative of the identification of the specific location and successive codes indicating the parameters that have reached an unacceptable deviation, said formatting means formatting both single digit and multiple digit status codes for use in establishing said digital status message, digital to multiple frequency (DTMF) conversion means for converting said digital status message generated by said formatting means to audio frequency signals for transmission over the telephone line to said remote communications equipment, and telephone interface means for interfacing between said DTMF conversion means and the telephone company line interconnected to the telephone central switching equipment and including relay controlled hook-switch contacts for selectively interconnecting said DTMF conversion means audio frequency output signals to said telephone line for application to the remote pager network communications equipment, said relay operable in response to an electrical control signal received from said CPU, wherein said CPU in response to said formatted digital status message reads digital signals stored in said memory means representative of a preselected number of pager telephone numbers and applies said digital signals in serial order to said DTMF conversion means for converting said signals representative of said pager telephone numbers to audio frequency signals for application through said telephone interface means and the telephone central switching equipment directly to the pager network communications equipment for automatically and sequentially dialing said preselected pager telephone numbers, and wherein said CPU further applies said digital status message in serial order to said DTMF conversion means for converting said digital signals to audio frequency signals for transmission over the telephone lines to the pager network communications equipment for broadcast to the paging devices for alphanumeric display of said digital status message therein in said preselected message format, and wherein said CPU automatically dials each of said pager telephone numbers a preselected number of times.

Claim 34

The telemetry unit as described in claim 29, wherein said current status signal reference is the last such status determined for each parameter and reported in a digital status message out through said communications means and then stored in said memory means.

Claim 35

The telemetry unit as described in claim 29, wherein said DTMF conversion means comprises a DTMF transceiver circuit.