Patent US4275445A successfully refreshed from Google Patents.
US4275445A
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Delayed action electrical protection device, depending on an adjusted magnitude
Assignee: Arteche Instrumentacion y Sistemas Electronicos SA
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Filing: 1979-04-05
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Granted: 1981-06-23
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Expires: 1999-04-05
Abstract
Abstract The invention relates to an electrical protection device. According to the invention an adjusted signal is monitored to detect the presence of unwanted disturbances. A microprocessor is used to calculate a delay time for tripping in accordance with the comparison of this signal to calculated values within the microprocessor.
Inventors
- 👤 Rodolfo Di Pietro Elizaran
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:50
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/08; H02H3/093; H02H3/0935; H02H3/02; H02H3/06; H02H3/07
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
116 words
A delayed action electrical protection device intended for protection of electrical lines and equipment against electrical disturbances comprising: (a) an analog-to-digital converter for converting an adjusted monitored signal to digital format signal; (b) a micro-processor for receiving said digital format signal and relating it to reference values from timing characteristic curves; (c) said micro-processor providing at least one relay tripping signal for electrical protection; and (d) said tripping signal being delayed by a varying amount according to the following formula: t.sub.a =(K/i.sup.2 -1) wherein t a =the delay time for actuating said tripping signal i=(I/I n ) I=the actual current of the monitored signal I n =a preset reference value of current and K=a predetermined constant.
Claim 2
Dependent Claim
116 words
A delayed action electrical protection device intended for protection of electrical lines and equipment against electrical disturbances comprising: (a) an analog-to-digital converter for converting an adjusted monitored signal to digital format signal; (b) a micro-processor for receiving said digital format signal and relating it to reference values from timing characteristic curves; (c) said micro-processor providing at least one relay tripping signal for electrical protection; and (d) said tripping signal being delayed by a varying amount according to the following formula: t.sub.a =(K/i.sup.2 -1) wherein t a =the delay time for actuating said tripping signal i=(I/I n ) I=the actual current of the monitored signal I n =a preset reference value of current and K=a predetermined constant.
Claim 3
Dependent Claim
116 words
The delayed action electrical protection device of claim 1 wherein the tripping signal delay time is updated according to the formula t a2 (remainder)=(1-(T 1 /t al )·t a2 wherein t a2 (remainder) denotes the time which must elapse before tripping at the second successive current ratio i 2 , where i is defined as in claim 1. T 1 is the elapsed time from the determination of i, where i 1 is the previous current ratio and i is defined as above; t al is the trip delay time based on the previous determination at i 1 ; and t a2 is the trip delay time which would exist had i 2 been present initially.
Claim 4
Independent Claim
100 words
A method for protecting electrical lines of equipment against electrical disturbances comprising the steps of: (a) monitoring the desired signal; (b) providing an adjusted magnitude signal derived from said desired signal; (c) converting said adjusted magnitude signal to a digital signal; (d) determining a delay time according to the formula : t.sub.a =K/(i.sup.2-1) wherein t a =the delay time for actuating said tripping signal i=I/I n I=the actual current of the monitored signal I n =a preset reference value of current and K=a predetermined constant; and (e) providing a tripping signal whenever the electrical disturbance extends beyond said delay time.
Claim 5
Independent Claim
100 words
A method for protecting electrical lines of equipment against electrical disturbances comprising the steps of: (a) monitoring the desired signal; (b) providing an adjusted magnitude signal derived from said desired signal; (c) converting said adjusted magnitude signal to a digital signal; (d) determining a delay time according to the formula : t.sub.a =K/(i.sup.2-1) wherein t a =the delay time for actuating said tripping signal i=I/I n I=the actual current of the monitored signal I n =a preset reference value of current and K=a predetermined constant; and (e) providing a tripping signal whenever the electrical disturbance extends beyond said delay time.
Claim 6
Dependent Claim
25 words
The method of claim 3 further comprising the step of instantaneously providing said tripping signal whenever a preset value of the adjusted magnitude is exceeded.
Claim 7
Dependent Claim
36 words
The method of claim 3 further comprising the steps of monitoring the adjusted magnitude to determine the direction of variation of said magnitude and providing said tripping signal if the variation is in the wrong direction.
Claim 8
Dependent Claim
27 words
The method of claim 5 further comprising the step of monitoring said adjusted magnitude after tripping and resetting said tripping signal after a predetermined time has elapsed.
Claim 9
Dependent Claim
21 words
The method of claim 3 further comprising the step of indicating the performance of the protection device by lighting light-emitting diodes.
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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) | 1984-06-22 | 1984-12-22 | 1985-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-22 | 1988-12-22 | 1989-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-22 | 1992-12-22 | 1993-06-23 | $7700.00 | Window Closed / Lapsed |