US4333050A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiphase voltage monitor
Assignee: Individual
•
Filing: 1980-02-26
•
Granted: 1982-06-01
•
Expires: 2000-02-26
Abstract
Abstract A monitor for a polyphase power line continuously compares the voltage on each phase of the power line with reference voltages that are selected percentages above and below the average of the power line voltages to detect voltage unbalance and with fixed voltages to detect high or low voltage conditions. The monitor is also responsive to phase sequence.
Inventors
- 👤 Maynard C. Yeasting
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:48
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/20; G; G01; G01R; G01R29/00; G01R29/16; G01R29/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
112 words
A voltage monitor for a multiphase electrical power supply comprising, in combination: (a) an AC to DC converter for each voltage being monitored, (b) a voltage limit generator that is connected to the converters and that has means for averaging the voltage outputs of the converters and delivering reference voltages that are selectable percentages above and below the average voltage, (c) a limit comparator connected to each converter and to the limit voltage generator for comparing the individual converter output with the reference voltages, and (d) utilization means connected to said comparators for signaling any excursion of a converter output voltage above the high reference voltage or below the low reference voltage.
Claim 2
Dependent Claim
112 words
A voltage monitor for a multiphase electrical power supply comprising, in combination: (a) an AC to DC converter for each voltage being monitored, (b) a voltage limit generator that is connected to the converters and that has means for averaging the voltage outputs of the converters and delivering reference voltages that are selectable percentages above and below the average voltage, (c) a limit comparator connected to each converter and to the limit voltage generator for comparing the individual converter output with the reference voltages, and (d) utilization means connected to said comparators for signaling any excursion of a converter output voltage above the high reference voltage or below the low reference voltage.
Claim 3
Dependent Claim
79 words
A voltage monitor according to claim 1 in which the voltage limit generator includes a voltage averaging network, an op-amp connected to the network, and a series of resistors connected between the output of the op-amp and ground in which the voltage at an intermediate junction of the series is fed back to the op-amp input, the voltage at the op-amp output is the high reference voltage and the voltage at another intermediate junction is the low reference voltage.
Claim 4
Dependent Claim
36 words
A voltage monitor according to claim 2 that includes a variable resistor connected between the high and low reference voltage junctions for simultaneously adjusting the percentage by which the reference voltages depart from the average voltage.
Claim 5
Dependent Claim
37 words
A voltage monitor according to claim 2 including means connected between said reference voltage junctions and said voltage comparator inputs for changing the voltages at the comparator inputs in response to an output signal of a comparator.
Claim 6
Dependent Claim
51 words
A voltage monitor according to claim 1 including a voltage sensitive switch connected to a standard voltage source, to said limit voltage generator, and to said limit comparators, arranged to switch the comparators from the limit voltage generator to the standard voltage source according to the magnitude of the average voltage.
Claim 7
Dependent Claim
41 words
A voltage monitor according to claim 1 in which the utilization means includes a plurality of light emitting diodes connected in series, and means connected to said comparators for bypassing current around selected diodes according to the indication to be presented.
Claim 8
Dependent Claim
45 words
In a voltage monitor according to claim 1, a latch circuit connected between said comparators and said utilization means, and a timer connected to the comparators and the latch circuit arranged to actuate the latch circuit a predetermined time after a comparator signals a fault.
References Cited (Backward Citations)
US3525019A
Cited
SU611270A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-31 | 1985-11-30 | 1986-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-31 | 1989-11-30 | 1990-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-31 | 1993-11-30 | 1994-06-01 | $7700.00 | Window Closed / Lapsed |