GB2118310A - An instrument for testing circuit breakers - Google Patents

An instrument for testing circuit breakers Download PDF

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Publication number
GB2118310A
GB2118310A GB08210418A GB8210418A GB2118310A GB 2118310 A GB2118310 A GB 2118310A GB 08210418 A GB08210418 A GB 08210418A GB 8210418 A GB8210418 A GB 8210418A GB 2118310 A GB2118310 A GB 2118310A
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GB
United Kingdom
Prior art keywords
instrument
circuit
circuit breaker
test
trip
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08210418A
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GB2118310B (en
Inventor
Ian Mackney Brooker
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Avo Ltd
Original Assignee
Avo Ltd
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Filing date
Publication date
Application filed by Avo Ltd filed Critical Avo Ltd
Priority to GB08210418A priority Critical patent/GB2118310B/en
Publication of GB2118310A publication Critical patent/GB2118310A/en
Application granted granted Critical
Publication of GB2118310B publication Critical patent/GB2118310B/en
Expired legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02—Details
    • H02H3/04—Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned
    • H02H3/044—Checking correct functioning of protective arrangements, e.g. by simulating a fault
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
    • G01R31/3277—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Breakers (AREA)
  • Emergency Protection Circuit Devices (AREA)

Abstract

An instrument 25 is connected to a circuit breaker 3 via a plug and socket connection 1. One of a number of test modes can be selected in accordance with the trip level current rating of the circuit breaker, 3, which can be set on the instrument 25. The selection of a particular mode connects a resistor 16, 17 or 18 and timing circuit 7 into circuit. By depressing a "TEST" push-button 9, a relay switch 8 is closed, thereby causing a predetermined leakage current iE. to flow to the circuit breaker 3. Neon lights 4, 5 and 6 indicate to a user whether or not the circuit breaker 3 has been caused to trip. A thermal fuse 22 gives protection to the user, should a fault occur within the instrument 25, thereby causing internal overheating. <IMAGE>

Description

SPECIFICATION An instrument for testing circuit breakers This invention relates two an instrumentfortesting circuit breakers, the instrument being particularly though not exclusively suitable fortesting residual current circuit breakers, which are otherwise known as earth leakage circuit breakers.
It is known to provide circuit breakers in an electrical installation, such as a lighting circuit, a complete ring-mains, or even a localised circuit breaker for a single socket outlet, to protect the installation.
A residual current circuit breaker operates by sensing a balance of currentflowing in the live and neutral wires of the installation it is protecting. When this balance is upset by a substantial amount of current leaking away to earth,the circuit breaker is tripped and thus breaks the electrical circuit of the installation.
Instruments for testing circuit breakers of thins type, which supply a leakage currentto the circuit breakerto produce a simulated fault condition, are also known.
When the supplied leakage current equals a set trip level current rating for the particular circuit breaker undertest, the circuit breaker should be tripped if it is functioning correctly.
The instrument may be required to be hand-held by an operator, which may impose a substantial level of danger own the operator, if a fault should occurwithin the instrument, as well as possibly causing irreparable damage to the actual instrument.
It is therefore an object of the present invention to provide an improved and substantially safer type of instrumentfortesting circuit breakers.
According to the invention there is provided an instrumentfortesting circuit breakers comprising circuit means for supplying a preselectable value of earth leakagecurrentfora predetermined length of timeto electrical wiring protected by the circuit breaker, display means indicative ofthe response of the circuit breakerto said value of earth leakage current, and protection means for responding to the attainment, by a component of said instrument, of a temperature indicative of a fault condition, to disconneck the instrumentfrom said wiring.
Further according to the invention there is provided an instrument as setforth in the immediately preceding paragraph including by-pass means for enabling the display means to indicate that said disconnection has occurred.
In a preferred embodiment ofthe invention the protection means comprises a thermal fuse which is responsive to heat generated by a flow of current through a resistor located adjacent thereto and the by-pass means comprises a by-pass resistor, which by-passes the thermal fuse once it has ruptured, so thatthe display means can still operate.
Thetesting instrument may also include a number of individually selectable modes oftesting the circuit breaker, such as a "no trip" mode, a "trip" mode and a "fasttrip" mode. In a "no trip" mode, a value of leakage current less than the set trip level current rating ofthe circuit breaker is supplied thereto for a predetermined length of time, so that the circuit breaker should not be tripped if it is functioning correctly. In a "trip" mode, a value of leakage current equal to the trip level current is supplied for a predetermined length of time, so thatthe circuit breaker should be tripped, and, in a "fast trip" mode, a relatively large set leakage current is supplied for a relatively short length of time, to test the reaction rate ofthe circuit breaker.Thus, the various modes of testing ensurethatthe circuit breaker is functioning correctly according to its set trip level current rating.
The invention will now be further described by way of example only with reference to the accompanying diagrams, wherein:- Figure 1 shows a schematic diagram of a residual current circuit breaker and a preferred embodiment of the present invention, and, - Figure 2 shows a circuit diagram ofthe embodiment shown in Figure 1.
Referring nowto Figure 1,athree-pin plug and socket is shown at 1 ,the plug being wired to a supply lead 2 connected to one end of an instrument 25, live wire L, neutral wire N and earth wire E being connected to their respective terminal 26. The socket is connected to a circuit breaker 3 which is to be tested.
Once an electrical connection has been made between plug and socket, "L-E" and "L-N" neon lights, 5 and 6 respectively, on the instrument 25 will be illuminated as long as the wiring has been correctly carried out.
The instrument is then set to the trip level current rating of the circuit breaker 3, which could be, for example, 6mA, 1 OmA, 30mA, 1 00mA, 300mAor 500mA, by using a first slider switch, which is not shown in Figure 1,onthetesting instrument.
If a "no trip" test mode is required a second slider switch, also not shown, is setto a "no trip" position.
This operation then closes contacts 10 and 13, which are both associated with the "no trip" test. "TEST" push-button 9 is then pressed by an operator, which causes relay switch 8 to close, thus connecting resistance load 16 across the live wire Land the earth wire E, the value ofthe resistance load being dependent on the preselected setting ofthetrip level current. This action therefore creates a defined fault condition by causing a leakage current BE to flow through the earth wire E and to the circuit breaker3.
During this time period, a sensor 19 within the circuit breaker 3 senses an imbalance of cu rrents iN a nd iL, flowing respectively through the neutral wire N and the live wire L. However, during the "no trip" test, a leakage current of only 50% of the preselected trip level current is supplied to the circuit breaker, so that it the circuit breaker is functioning properly, it should not be tripped underthistest.
Also during the period of testing, the "L-E" and "L-N" lights, 5 and 6 respectively, are extinguished and a "TEST" light 4 is illuminated.
Once closed, opening ofthe relay switch 8 is governed entirely by a timing circuit7, which under this "no trip" test opens the relay switch after a period The drawing(s) originally filed were informal and the print here reproduced is taken from a later filed formal copy.
of 100 ms, thus stopping leakage current iE from flowing.
"TEST" light 4 is then extinguished and the fact that the circuit breaker has not tripped will be confirmed by the re-illumination of both the "L-E" and "L-N" lights, 5and6.
Within the timing circuit 7, there is a delay circuit (not shown), which prevents the push-button 9 reclosing the relay switch 8 before approximately one second has elapsed. This delay is to guard the circuit against too rapid a test repetition.
A ceramic fuse is shown at 21 and, connected in series with this, is a thermal fuse 22, which is designed to give protection to the operator, should a fault occur within the circuit in the instrument 25, thus causing internal overheating. The thermal fuse 22 will be ruptured by a build-up of heat generated by an adjacent resistor 23, which will occur once a fault develops.
Afuse by-pass resistor 24 is also provided, so that even when a fuse has ruptured, lights 5 and 6 will still be illuminated, although at a substantially lower intensity than under normal operating conditions when the instrument is functioning properly, to show if the socket is "live". The fact that the fuse has ruptured will also be indicated to the operator by the pressing of push-button being ineffective in initiating afurthertest period.
If a "trip" test mode is required, then the second slider switch (notshown) issetto a "trip" position, which closes contacts 11 and 14. When "TEST" push-button 9 is pressed, relay switch 8 is closed, thus connecting resistance load 17 across live wire Land earth wire E. "L-E" light 5 and "L-N" light 6 wiil then be extinguished and "TEST" light 4will be illuminated.
However, during this test, a leakage current E equal to the preselected trip level current will flow for 100 ms. The imbalance of currents 1N and iLwill be sensed by the sensor 19 and the circuit breaker should be tripped, thus opening contacts 20 and breaking the circuit to the socket. The fact that the circuit breakers has tripped will be confirmed by the "L-E" and "L-N" lights remaining extinguished afterthetest period is over and relay switch 8 has been opened again. The circuit breaker can then be re-set manually.
If a "fast trip" test is required, the second slider switch is set to a "fast trip" position and push-button 9 is pressed. This then closes contacts 12 and 15 and connects resistance load 18 across the live wire Land the earth wire E. The sequence of operation is the same as for the "trip" test, but a fixed leakage current of 250 mA is supplied to the circuit breakerforonly40 ms to test the reaction rate thereof.
The "fast trip" test will normally only be needed on circuit breakers which are designed to reduce the risk of a fatal electric shock by direct electrical contact with live parts of the plug and socket, and such circuit breakers usually have a low trip level current rating of 30 mA or less.
Figure 2 shows a circuit lay-outforthe instrument 25 shown in Figure 1, and like parts in Figure 2 are labelled with like reference numerals with respectto Figure 1. Figure2 also showsthethermal fuse 22, the adjacent resistor 23 and the by-pass resistor 24.
The two slider switches referred to in the above description ofthe operation of the instrumentcan now be seen at 27, which shows a first slider switch to set the trip level current rating of the circuit breaker to be tested, and at 28, which shows a second slider switch to set the required test mode.
The instrument operates from the mains power supplywhich incorporates the circuit breaker being tested. The mains supply voltage to the instrument is reduced through atransformer29, rectified and smoothed before feeding the timing circuit 7. In one example, a chip of type T555 is used forthe timing circuit.
The resistance load is made up of a combination of resistors, shown generally at 30, which are chosen so thatthey pass the required trip level current, or 50% of it, or 250 mA, depending ofthe particulartestwhich has been selected, when they are connected across the mains supply.
Once the thermal fuse has ruptured, it cannot be replaced bythe operatorfor reasons of safety, asthe cause of overheating within the instrument should be established by a skilled person priorto replacement of thefuse.
Due to the nature of the circuit, the actual value of the leakage current depends on the value ofthe supply voltage as well as the tolerance of the resistance load, so that, as the mains supply voltage varies, there will be a corresponding variation in the accuracy of the testing instrument.
It will also be appreciated that any of a number of alternative electrical connections could be used between the circuit breaker and the instrument, instead of a three-pin plug and socket. For instance, insulated crocodile clips may be fitted to the supply lead for direct connection to the circuit breaker.
This invention therefore provides a light-weight, hand-held instrumentfortesting circuit breakers, which is preferably enclosed within a robust, plastics casing, incorporating a safety device to protect the operator and/or the instrument from any fau It occurring therewithin, which would lead to internal overheating.
CLAIMS (Filed on 7/4/83).
1. An instrumentfortesting circuit breakers comprising circuit meansforsupplying a preselectable value of earth leakage currentfor a predetermined length oftimeto electrical wiring protected by the circuit breaker, display means indicative ofthe response of the circuit breaker to said value of earth leakage current, and protection means for responding to the attainment, by a component of said instrument, of a temperature indicative of a fault condition, to disconnect the instrument from said wiring.
2. An instrument as claimed in claim 1 including by-pass means for enabling the display means to indicate that said disconnection has occurred.
3. An instrument as claimed in claim 2 wherein said by-pass means comprises a by-pass resistor which by-passes the protection means, so that the display means can maintain operation.
4. An instrument as claimed in any preceding claim wherein said protection means comprises a thermal fuse which is responsive to heat generated by a flow of current through a resistor located adjacent thereto.
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. of 100 ms, thus stopping leakage current iE from flowing. "TEST" light 4 is then extinguished and the fact that the circuit breaker has not tripped will be confirmed by the re-illumination of both the "L-E" and "L-N" lights, 5and6. Within the timing circuit 7, there is a delay circuit (not shown), which prevents the push-button 9 reclosing the relay switch 8 before approximately one second has elapsed. This delay is to guard the circuit against too rapid a test repetition. A ceramic fuse is shown at 21 and, connected in series with this, is a thermal fuse 22, which is designed to give protection to the operator, should a fault occur within the circuit in the instrument 25, thus causing internal overheating. The thermal fuse 22 will be ruptured by a build-up of heat generated by an adjacent resistor 23, which will occur once a fault develops. Afuse by-pass resistor 24 is also provided, so that even when a fuse has ruptured, lights 5 and 6 will still be illuminated, although at a substantially lower intensity than under normal operating conditions when the instrument is functioning properly, to show if the socket is "live". The fact that the fuse has ruptured will also be indicated to the operator by the pressing of push-button being ineffective in initiating afurthertest period. If a "trip" test mode is required, then the second slider switch (notshown) issetto a "trip" position, which closes contacts 11 and 14. When "TEST" push-button 9 is pressed, relay switch 8 is closed, thus connecting resistance load 17 across live wire Land earth wire E. "L-E" light 5 and "L-N" light 6 wiil then be extinguished and "TEST" light 4will be illuminated. However, during this test, a leakage current E equal to the preselected trip level current will flow for 100 ms. The imbalance of currents 1N and iLwill be sensed by the sensor 19 and the circuit breaker should be tripped, thus opening contacts 20 and breaking the circuit to the socket. The fact that the circuit breakers has tripped will be confirmed by the "L-E" and "L-N" lights remaining extinguished afterthetest period is over and relay switch 8 has been opened again. The circuit breaker can then be re-set manually. If a "fast trip" test is required, the second slider switch is set to a "fast trip" position and push-button 9 is pressed. This then closes contacts 12 and 15 and connects resistance load 18 across the live wire Land the earth wire E. The sequence of operation is the same as for the "trip" test, but a fixed leakage current of 250 mA is supplied to the circuit breakerforonly40 ms to test the reaction rate thereof. The "fast trip" test will normally only be needed on circuit breakers which are designed to reduce the risk of a fatal electric shock by direct electrical contact with live parts of the plug and socket, and such circuit breakers usually have a low trip level current rating of 30 mA or less. Figure 2 shows a circuit lay-outforthe instrument 25 shown in Figure 1, and like parts in Figure 2 are labelled with like reference numerals with respectto Figure 1. Figure2 also showsthethermal fuse 22, the adjacent resistor 23 and the by-pass resistor 24. The two slider switches referred to in the above description ofthe operation of the instrumentcan now be seen at 27, which shows a first slider switch to set the trip level current rating of the circuit breaker to be tested, and at 28, which shows a second slider switch to set the required test mode. The instrument operates from the mains power supplywhich incorporates the circuit breaker being tested. The mains supply voltage to the instrument is reduced through atransformer29, rectified and smoothed before feeding the timing circuit 7. In one example, a chip of type T555 is used forthe timing circuit. The resistance load is made up of a combination of resistors, shown generally at 30, which are chosen so thatthey pass the required trip level current, or 50% of it, or 250 mA, depending ofthe particulartestwhich has been selected, when they are connected across the mains supply. Once the thermal fuse has ruptured, it cannot be replaced bythe operatorfor reasons of safety, asthe cause of overheating within the instrument should be established by a skilled person priorto replacement of thefuse. Due to the nature of the circuit, the actual value of the leakage current depends on the value ofthe supply voltage as well as the tolerance of the resistance load, so that, as the mains supply voltage varies, there will be a corresponding variation in the accuracy of the testing instrument. It will also be appreciated that any of a number of alternative electrical connections could be used between the circuit breaker and the instrument, instead of a three-pin plug and socket. For instance, insulated crocodile clips may be fitted to the supply lead for direct connection to the circuit breaker. This invention therefore provides a light-weight, hand-held instrumentfortesting circuit breakers, which is preferably enclosed within a robust, plastics casing, incorporating a safety device to protect the operator and/or the instrument from any fau It occurring therewithin, which would lead to internal overheating. CLAIMS (Filed on 7/4/83).
1. An instrumentfortesting circuit breakers comprising circuit meansforsupplying a preselectable value of earth leakage currentfor a predetermined length oftimeto electrical wiring protected by the circuit breaker, display means indicative ofthe response of the circuit breaker to said value of earth leakage current, and protection means for responding to the attainment, by a component of said instrument, of a temperature indicative of a fault condition, to disconnect the instrument from said wiring.
2. An instrument as claimed in claim 1 including by-pass means for enabling the display means to indicate that said disconnection has occurred.
3. An instrument as claimed in claim 2 wherein said by-pass means comprises a by-pass resistor which by-passes the protection means, so that the display means can maintain operation.
4. An instrument as claimed in any preceding claim wherein said protection means comprises a thermal fuse which is responsive to heat generated by a flow of current through a resistor located adjacent thereto.
5. An instrument as claimed in any preceding
claim and urther:ncludlng user-operable means for selecting one of a number of individually selectable modes of testing the circuit breaker, each mode being arranged respectivelyto supply a predetermined value of said earth leakage currentforsaid predetermined length of time to said electrical wiring, thereby enabling a set trip level current rating of the circuit breakerto be tested.
6. An instrument as claimed in claimS wherein said user-operable means comprises at least one slider switch.
7. An instrument as claimed in any preceding claim wherein said instrument is connected to said electrical wiring protected by the circuit breaker via a plug and socket connection.
8. An instrument substantially as herein described with reference to the accompanying diagrams.
GB08210418A 1982-04-08 1982-04-08 An instrument for testing circuit breakers Expired GB2118310B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB08210418A GB2118310B (en) 1982-04-08 1982-04-08 An instrument for testing circuit breakers

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB08210418A GB2118310B (en) 1982-04-08 1982-04-08 An instrument for testing circuit breakers

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GB2118310A true GB2118310A (en) 1983-10-26
GB2118310B GB2118310B (en) 1986-01-02

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2616917A1 (en) * 1987-06-17 1988-12-23 Gen Electric TEST DEVICE FOR CIRCUIT BREAKER
WO2006128233A1 (en) * 2005-06-01 2006-12-07 Easytest Pty Ltd An apparatus and method for testing circuit breakers
WO2007123390A1 (en) * 2006-04-26 2007-11-01 See Ni Fong A time alert device for use together with an earth leakage protection device
GB2456799A (en) * 2008-01-24 2009-07-29 Andrew Abbott Residual current device test actuator
WO2011041835A1 (en) * 2009-10-06 2011-04-14 Easytest Pty Ltd Portable earth leakage tester
CN104267344A (en) * 2014-10-27 2015-01-07 国家电网公司 Breaker trip detection method based on predicated mutation information
CN106168650A (en) * 2016-08-30 2016-11-30 中山市开普电器有限公司 A kind of specified residue connects breaking capacity test device
CN106646209A (en) * 2016-10-31 2017-05-10 中国电力科学研究院 High and low temperature trip intelligent test device for cost-control circuit breaker
CN106771751A (en) * 2016-12-27 2017-05-31 浙江电力变压器有限公司温州昌泰电力开关分公司 A kind of portable distribution automation prepackage debugging test case
CN108181581A (en) * 2018-03-19 2018-06-19 山东省产品质量检验研究院 The intelligent test device and test method of a kind of residual current action protector
CN109030914A (en) * 2018-08-24 2018-12-18 海盐新跃电器有限公司 A kind of circuit of software optimization detection waveform output
CN111537870A (en) * 2020-04-03 2020-08-14 江苏能电科技有限公司 Circuit breaker electric leakage testing method, system, equipment and medium

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1449648A (en) * 1972-12-20 1976-09-15 Vitrohm Gmbh Co Kg Protective device comprising an electrical ressitor
GB1499616A (en) * 1975-09-11 1978-02-01 Allen Bradley Co Resistors with an integral thermal fuse
GB1540088A (en) * 1977-04-04 1979-02-07 Beswick Ltd K Fusible power resistors
GB1559535A (en) * 1976-02-10 1980-01-23 Email Ltd Electrical test unit
GB2056094A (en) * 1979-07-26 1981-03-11 Kodak Ltd Earth leakage circuit breaker tester
GB2072861A (en) * 1980-02-23 1981-10-07 Redsure Elp Ltd Earth leakage circuit breaker tester

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1449648A (en) * 1972-12-20 1976-09-15 Vitrohm Gmbh Co Kg Protective device comprising an electrical ressitor
GB1499616A (en) * 1975-09-11 1978-02-01 Allen Bradley Co Resistors with an integral thermal fuse
GB1559535A (en) * 1976-02-10 1980-01-23 Email Ltd Electrical test unit
GB1540088A (en) * 1977-04-04 1979-02-07 Beswick Ltd K Fusible power resistors
GB2056094A (en) * 1979-07-26 1981-03-11 Kodak Ltd Earth leakage circuit breaker tester
GB2072861A (en) * 1980-02-23 1981-10-07 Redsure Elp Ltd Earth leakage circuit breaker tester

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2616917A1 (en) * 1987-06-17 1988-12-23 Gen Electric TEST DEVICE FOR CIRCUIT BREAKER
US4814712A (en) * 1987-06-17 1989-03-21 General Electric Company Test kit for a circuit breaker containing an electronic trip unit
WO2006128233A1 (en) * 2005-06-01 2006-12-07 Easytest Pty Ltd An apparatus and method for testing circuit breakers
AU2006254720B2 (en) * 2005-06-01 2010-06-03 Easytest Pty Ltd An apparatus and method for testing circuit breakers
WO2007123390A1 (en) * 2006-04-26 2007-11-01 See Ni Fong A time alert device for use together with an earth leakage protection device
US8232804B2 (en) 2006-04-26 2012-07-31 See Ni Fong Time alert device for use together with an earth leakage protection device
GB2456799A (en) * 2008-01-24 2009-07-29 Andrew Abbott Residual current device test actuator
WO2011041835A1 (en) * 2009-10-06 2011-04-14 Easytest Pty Ltd Portable earth leakage tester
CN104267344A (en) * 2014-10-27 2015-01-07 国家电网公司 Breaker trip detection method based on predicated mutation information
CN104267344B (en) * 2014-10-27 2017-01-18 国家电网公司 Breaker trip detection method based on predicated mutation information
CN106168650A (en) * 2016-08-30 2016-11-30 中山市开普电器有限公司 A kind of specified residue connects breaking capacity test device
CN106646209A (en) * 2016-10-31 2017-05-10 中国电力科学研究院 High and low temperature trip intelligent test device for cost-control circuit breaker
CN106646209B (en) * 2016-10-31 2023-12-05 中国电力科学研究院 Intelligent testing equipment for high-temperature and low-temperature tripping of charge control circuit breaker
CN106771751A (en) * 2016-12-27 2017-05-31 浙江电力变压器有限公司温州昌泰电力开关分公司 A kind of portable distribution automation prepackage debugging test case
CN106771751B (en) * 2016-12-27 2023-09-15 浙江电力变压器有限公司温州昌泰电力开关分公司 Automatic preassemble debugging test box of mobile distribution network
CN108181581A (en) * 2018-03-19 2018-06-19 山东省产品质量检验研究院 The intelligent test device and test method of a kind of residual current action protector
CN108181581B (en) * 2018-03-19 2023-12-22 山东省产品质量检验研究院 Intelligent testing device and testing method for residual current operated protector
CN109030914A (en) * 2018-08-24 2018-12-18 海盐新跃电器有限公司 A kind of circuit of software optimization detection waveform output
CN111537870A (en) * 2020-04-03 2020-08-14 江苏能电科技有限公司 Circuit breaker electric leakage testing method, system, equipment and medium

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