SE447684B - FELSTROMSSKYDDSOMKOPPLARE - Google Patents
FELSTROMSSKYDDSOMKOPPLAREInfo
- Publication number
- SE447684B SE447684B SE8104979A SE8104979A SE447684B SE 447684 B SE447684 B SE 447684B SE 8104979 A SE8104979 A SE 8104979A SE 8104979 A SE8104979 A SE 8104979A SE 447684 B SE447684 B SE 447684B
- Authority
- SE
- Sweden
- Prior art keywords
- current
- residual current
- tripping
- residual
- connection
- Prior art date
Links
- 238000004804 winding Methods 0.000 claims description 11
- 238000004146 energy storage Methods 0.000 claims description 8
- 230000006698 induction Effects 0.000 claims description 7
- 239000003990 capacitor Substances 0.000 claims description 6
- 239000000696 magnetic material Substances 0.000 claims description 4
- 239000004065 semiconductor Substances 0.000 claims description 4
- 230000003213 activating effect Effects 0.000 claims description 3
- 230000001419 dependent effect Effects 0.000 claims description 2
- 239000011810 insulating material Substances 0.000 claims 1
- 230000004913 activation Effects 0.000 description 4
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 230000002349 favourable effect Effects 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 238000009434 installation Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H83/00—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current
- H01H83/02—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current operated by earth fault currents
-
- 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
- H02H3/26—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 responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents
- H02H3/32—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 responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors
- H02H3/33—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 responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors using summation current transformers
- H02H3/332—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 responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors using summation current transformers with means responsive to dc component in the fault current
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Breakers (AREA)
- Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
- Emergency Protection Circuit Devices (AREA)
- Ignition Installations For Internal Combustion Engines (AREA)
Description
447 684 2 ningsenergin var väsentligt högre än vid de direkta kopplin- garna utan elektriska energimatningskopplingar, ledde konkur- rensen med trenden till allt lägre priser och mindre dimensio- ner för felströmsskyddsomkopplarna till att pulsutlösningen endast användes för specialomkopplare (t.ex. nollednings- skyddsomkopplare). I denna konkurrens användes då även osak- liga argument, exempelvis kravet på extremt korta frånkopp- lingstider, vilket principiellt leder till svårigheter vid matnings- eller lagringskopplingar. I dag vet man på grund av resultaten från den moderna elektropatologin att frånkopp- lingstiden för skyddsomkopplaren inte har någon särskild bety- delse för skyddet mot direkt och vid indirekt beröring, så länge som den är mindre än 0,2 sekunder. Allt för korta från- kopplíngstider och onödigt hög utlösningskänslighet leder endast till felutlösning genom i och för sig tillåtna avled- ningsströmmar eller vid koppling av kablar och vid uppträdande av atmosfäriska överspänningar. Speciellt i friledningsnät har därigenom ekonomiska skador uppkommit (frysbehållare). 447 684 2 energy was significantly higher than with the direct connections without electrical energy supply connections, the competition with the trend led to ever lower prices and smaller dimensions for the residual current circuit breakers, so that the pulse tripping was only used for special switches (eg neutral circuit protection switches ). In this competition, unreasonable arguments were also used, for example the requirement for extremely short disconnection times, which in principle leads to difficulties in supply or storage connections. Today, due to the results of modern electropathology, it is known that the switch-off time of the protection switch has no special significance for protection against direct and indirect contact, as long as it is less than 0.2 seconds. Excessively short disconnection times and unnecessarily high tripping sensitivity only lead to faulty tripping through per se permitted discharge currents or when connecting cables and when atmospheric overvoltages occur. Especially in free-range networks, this has resulted in financial damage (freezer containers).
Väsentligt viktigare är funktionssäkerheten för skyddsom- kopplaren, och här har den ovan skildrade utvecklingen visat ogynnsamma resultat. Man har alltid utvecklat känsligare ut- lösare, varvid tillverkningsproblemen och miljöinverkan knappast längre kan behärskas. I dag visar kontrollerna av anläggningarna att några procent av de inbyggda felströms- skyddsomkopplarna ej är funktionsdugliga. Detta är ett ohåll- bart läge som ger anledning till större omsorg.Significantly more important is the functional safety of the protection switch, and here the development described above has shown unfavorable results. More sensitive triggers have always been developed, whereby manufacturing problems and the environmental impact can hardly be controlled anymore. Today, the inspections of the plants show that a few percent of the built-in residual current circuit-breaker switches are not functional. This is an unsustainable situation that gives rise to greater care.
En lösning på detta allvarliga problem medför å ena sidan införingen av nollan, vilken tillsammans med felströmsskydds- omkopplare möjliggör en ytterst högvärdig och tillförlitlig skyddsåtgärd i form av den sdm nollskyddskopplingen, och å andra sidan i nät, i vilka nollan ej är tillåten, seriekopp- lingen av två felströmsskyddsomkopplare. I princip skall där- vid den sist kopplade omkopplaren kopplas selektivt, dans. vid ett fel frånkopplas endast den av densamma skyddade in- stallationen och den först kopplade kopplaren, som i fördel- ningen skyddar flera anläggningsdelar, förblir inkopplad.A solution to this serious problem entails, on the one hand, the introduction of the zero, which together with a residual current circuit breaker enables an extremely high-quality and reliable protection measure in the form of the sdm neutral protection connection, and on the other hand in networks in which the zero is not permitted, series connection of two residual current circuit breakers. In principle, the last connected switch must be connected selectively, dance. in the event of a fault, only the installation protected by it is switched off and the first connected coupler, which in the distribution protects several system parts, remains switched on.
Detta krav kan på enkelt sätt uppfyllas av energilagringskopp- lingen. Denna koppling undviker även ovannämnda felutlösningar J) 447 684 3 vid atmosfäriska överspänningar, ja den möjliggör t.o.m. in- byggnad av överspänningsavledare efter FI-skyddsomkopplarna.This requirement can easily be met by the energy storage connection. This coupling also avoids the above-mentioned fault triggers J) 447 684 3 at atmospheric overvoltages, yes it enables t.o.m. installation of surge arresters after the FI protection switches.
Under aktiveringen av överspänningsavledarna flyter ju ström under kort tid (under 10 ms) till jord, genom FI-skyddsomkopp- laren med direkt utlösning utan elektrisk energilagringskopp- ling för frånkoppling.During the activation of the surge arresters, current flows for a short time (less than 10 ms) to earth, through the FI protection switch with direct tripping without electrical energy storage connection for disconnection.
Nu är det så, att lämpliga halvledarbyggelement, som är billiga och har små dimensioner och kan ersätta glimlamporna som kopplingselement, varit tillgängliga endast under senare tid. Med kopplingsspänningar som ligger kring tio volt möjlig- gör de små sekundärvarvtal i summaströmomvandlaren och nästan godtyckliga utlösningskaraktäristikor för skyddsomkopplaren.Now it is the case that suitable semiconductor building elements, which are inexpensive and have small dimensions and can replace the glow lamps as coupling elements, have only been available recently. With switching voltages around ten volts, they enable small secondary speeds in the sum current converter and almost arbitrary tripping characteristics for the protection switch.
För att även kondensatorn skall hållas liten används med för- del permanentmagnetutlösare, vilka man kan inställa mindre kri- tiskt och vilka man kan låta arbeta med större utlösnings- krafter än vid de direkta kopplingarna utan elektrisk energi- lagringskoppling. För att uppnå en vid ekonomiska grunddimen- sioner för summaströmomvandlaren för beröringsskyddet gynnsam form av FI-skyddsomkopplarens utlösningskaraktäristik förses enligt uppfinningen sekundärlindningen med ett lindningsvarv- tal, som ligger över 100. Permanentmagnetutlösarens aktive- ringslindning måste förses med ett lindningstal, som för den använda felströmsutlösaren vid urladdningen av kondensatorn ger den gynnsammaste formen för utlösningspulsen. Detta är enklast möjligt med den s.k. polariserade permanentmagnetutlö- saren, vars aktiveringskrets uppvisar en luftspaltl Därigenom kan aktiveringslindningen framställas i lindningsmaskiner och tillverkningen i hög grad automatiseras.In order to keep the capacitor small, permanent magnet triggers are used to advantage, which can be set less critically and which can be operated with greater tripping forces than with the direct connections without electrical energy storage connection. In order to achieve a favorable form of the FI protection switch's tripping characteristic in the basic economic dimensions of the sum current converter for the contact protection, the secondary winding according to the invention is provided with a winding speed exceeding 100. The permanent magnet trigger activation winding must be provided with a when discharging the capacitor gives the most favorable shape of the trip pulse. This is most easily possible with the so-called polarized permanent magnet trigger, the activation circuit of which has an air gap. As a result, the activation winding can be produced in winding machines and the production is highly automated.
Det moderna konceptet för en felströmsskyddsomkopplare måste dock även behärska utlösning vid pulserande likströmmar.However, the modern concept of a residual current circuit breaker must also control tripping at pulsating direct currents.
Det har ju varit känt att FI-skyddsomkopplare endast kan vara verksamma vid växelström. Om felströmmen har strömkomponenter påverkas skyddsomkopplaren ogynnsamt vad gäller dess utlös- ningskänslighet. Då allt fler elektroniska byggelement används i hushållsapparater måste emellertid även likströmsproblemet lösas, varvid det visar sig att vid de i praktiken vid elekt- riska hushållsapparater använda kopplingarna vid en kropps- strömslutning den flytande felsltrömmen alltid endast kan upp- 447 684 4 träda i form av en pulserande likström.It has been known that FI protection switches can only operate at alternating current. If the fault current has current components, the protection switch is adversely affected in terms of its trip sensitivity. However, as more and more electronic building elements are used in household appliances, the direct current problem must also be solved, whereby it turns out that in the case of the connections used in electrical household appliances in the event of a body current closure, the liquid fault current can always only occur in the form of a pulsating direct current.
Under de senaste åren har magnetmaterial utvecklats, vid vilka trots relativt hög permeabilitet skillnaden mellan induktionen i remanensen och i mättningen är hög. Dans., sta- tiskt uppmätt uppgår remanensinduktionen till mindre än 40 % av mättningsinduktionen. Med detta material är det möjligt att visserligen vid mindre utlösningskänslighet ändock åstadkomma funktionsduglighet av FI-skyddsomkopplare vid felströmmar i form av pulserande likströmmar. Eftersom då den inducerade spänningen i sekundärlindningen vid samma effektivvärde av primärströmmen är mindre än vid sinusformig växelström, kan här energilagringskopplingen medföra ett gynnsammare utlös- ningsförhållande. Framför allt förblir energiinnehållet i ut- lösningspulserna, vilka är givna genom halvledarelementets kopplingsspänning, lika och därmed även utlösningens tillför- litlighet.In recent years, magnetic materials have been developed in which, despite relatively high permeability, the difference between the induction in the residue and in the saturation is high. Dans., Statically measured, the residue induction amounts to less than 40% of the saturation induction. With this material, it is possible, although with less trip sensitivity, to still achieve the functionality of FI protection switches in the event of fault currents in the form of pulsating direct currents. Since then the induced voltage in the secondary winding at the same effective value of the primary current is less than at sinusoidal alternating current, here the energy storage coupling can lead to a more favorable tripping ratio. Above all, the energy content of the tripping pulses, which are given by the switching voltage of the semiconductor element, remains the same and thus also the reliability of the tripping.
Enligt uppfinningen innehåller sålunda det moderna kon- ceptet av en felströmsskyddsomkopplare en omkopplare med en nätspänningsoberoende elektronisk energilagringskoppling i ut- lösningskretsen, en summaströmomvandlare med en kärna av ett högpermeabelt magnetmaterial med stor skillnad mellan remanens och mättningsinduktion och en permanentmagnetutlösare, som företrädesvis är utbildad såsom polariserad utlösare.Thus, according to the invention, the modern concept of a residual current circuit breaker includes a switch with a mains voltage independent electronic energy storage circuit in the tripping circuit, a sum current converter with a core of a high permeable magnetic material with a large difference between remanence and saturation. trigger.
Fig. 1 visar en exemplifierande utföringsform av uppfin- ningen. FI-skyddsomkopplarens kontaktapparat l in- resp. ur- kopplas över skyddslåset 2 med hjälp av manövreringsorganet 3 eller felströmsutlösaren 8. Felströmsutlösarens 8 aktiverings- lindning är över det spänningsberoende kopplingsorganet 7, som visas såsom halvledarbyggelement, förbunden med pulskondensa- torn 5. Denna uppladdas över likströmskopplingen 6 av summa- strömomvandlarens 4 sekundärlindning i beroende av höjden av den flytande felströmmen. Summaströmomvandlarens kärna 9 är framställd av ett högpermeabelt magnetiskt material, vars remanensinduktion är mindre än 40 % av mättningsinduktionen.Fig. 1 shows an exemplary embodiment of the invention. The FI protection switch's contact device l in- resp. is disconnected over the protective lock 2 by means of the actuator 3 or the residual current current trigger 8. The activating winding of the residual current current circuit 8 is via the voltage-dependent coupling means 7, which is shown as a semiconductor building element, connected to the pulse capacitor 5. depending on the height of the floating fault current. The core 9 of the sum current converter is made of a highly permeable magnetic material, the residual induction of which is less than 40% of the saturation induction.
Fig. 2 visar såsom ytterligare exempel på uppfinningen en utlösningskrets, vid vilken pulskondensatorn 5 över en spän- ningsfördubblingskoppling uppladdas från summaströmomvand- larens 4 sekundärlindning. Såsom utlösare används en polarise- 447 684 5 rad utlösare, som har en luftspalt i aktiveringskretsen mellan polskorna 10 och ankaret ll, så att vid avlyft ankare lind- ningen 12 i färdiglindat tillstånd kan anbringas på polskorna.Fig. 2 shows as a further example of the invention a tripping circuit, in which the pulse capacitor 5 is charged via a voltage doubling connection from the secondary winding of the sum current converter 4. As a trigger, a polarized trigger is used, which has an air gap in the activating circuit between the pole shoes 10 and the armature 11, so that when the anchor is lifted, the winding 12 can be applied to the pole shoes in the fully wound state.
Claims (3)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT0426180A ATA426180A (en) | 1980-08-21 | 1980-08-21 | Fault current protection switch |
Publications (2)
Publication Number | Publication Date |
---|---|
SE8104979L SE8104979L (en) | 1982-02-22 |
SE447684B true SE447684B (en) | 1986-12-01 |
Family
ID=3561715
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
SE8104979A SE447684B (en) | 1980-08-21 | 1981-08-21 | FELSTROMSSKYDDSOMKOPPLARE |
Country Status (10)
Country | Link |
---|---|
AT (1) | ATA426180A (en) |
BE (1) | BE890026A (en) |
CH (1) | CH655411B (en) |
DE (1) | DE3129277A1 (en) |
ES (1) | ES8204223A1 (en) |
FR (1) | FR2489038B1 (en) |
GB (1) | GB2082408B (en) |
IT (1) | IT1143408B (en) |
NL (1) | NL8102641A (en) |
SE (1) | SE447684B (en) |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2502393B1 (en) * | 1981-03-19 | 1986-08-08 | Etude Et Realisa De Disjoncteu | FAULT CURRENT DETECTION DEVICE |
AT383906B (en) * | 1985-04-16 | 1987-09-10 | Cti Ges Zur Pruefung Elektrote | Fault current protection switch for fault change and fault current |
AT387675B (en) * | 1987-04-02 | 1989-02-27 | Cti Ges Zur Pruefung Elektrote | Fault current protection switch with short delay |
DE4232702A1 (en) * | 1992-09-30 | 1994-03-31 | Abb Patent Gmbh | Residual current or residual current circuit breaker |
DE4429007A1 (en) | 1994-08-16 | 1996-02-22 | Siemens Ag | Residual current circuit breaker with energy storage circuit |
ATE161666T1 (en) * | 1994-09-14 | 1998-01-15 | Siemens Ag | RESIDUAL CURRENT BREAKER WITH ENERGY STORAGE CIRCUIT |
EP0797282B1 (en) * | 1996-03-18 | 2002-07-17 | Siemens Aktiengesellschaft | Ground fault circuit interrupter with energy storage circuit |
DE19739822A1 (en) * | 1997-09-11 | 1999-03-18 | Abb Patent Gmbh | Residual current circuit breaker |
AT406431B (en) * | 1998-01-28 | 2000-05-25 | Felten & Guilleaume Ag Oester | DEVICE FOR ANALYZING EARTH FAULT CURRENTS APPLICABLE IN AN ELECTRICAL SYSTEM AND BY THIS CONTROLLED SWITCHGEAR |
DE19833829A1 (en) * | 1998-07-28 | 2000-02-03 | Abb Patent Gmbh | Tripping device for a residual current circuit breaker and circuit arrangement for controlling the same |
FR3086062A1 (en) * | 2018-09-18 | 2020-03-20 | Soreel Societe De Realisation D'equipements Electriques | DEVICE FOR CONTROLLING A CUT-OFF MEMBER OF AN ELECTRICAL INSTALLATION AND METHOD FOR TESTING SUCH A DEVICE |
EP3627164B1 (en) * | 2018-09-18 | 2023-08-09 | Soreel Societe de Realisation d'Equipements Electriques | System comprising a device for controlling a high-speed circuit breaker of an electrical installation and method for testing such a system |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB841181A (en) * | 1957-03-02 | 1960-07-13 | Biegelmeier Gottfried | Improvements in and relating to protective circuit-breakers |
FR1202203A (en) * | 1957-03-02 | 1960-01-08 | Protection devices for an electrical installation | |
AT197468B (en) * | 1957-03-02 | 1958-04-25 | Biegelmeier Gottfried | Residual voltage or residual current protection circuit |
FR1267270A (en) * | 1960-06-09 | 1961-07-21 | Electronique Et D Automatique | Control device for a protection relay for an electrical power supply circuit |
BE628958A (en) * | 1962-02-28 | |||
FR1369817A (en) * | 1962-10-20 | 1964-08-14 | Process for the manufacture of flame retardant fibrous masses containing cellulose | |
FR1411747A (en) * | 1964-07-15 | 1965-09-24 | Electronique Et D Automatique | Improvements to protective devices against earth fault currents in power supply circuits |
FR1523445A (en) * | 1967-03-23 | 1968-05-03 | Comp Generale Electricite | Circuit breaker incorporating a semiconductor threshold element |
CH475661A (en) * | 1968-11-06 | 1969-07-15 | Landis & Gyr Ag | Residual current circuit breaker |
US3535590A (en) * | 1968-12-09 | 1970-10-20 | Ferdy Mayer | High sensitivity electromechanical actuators |
DE2044302B2 (en) * | 1970-09-08 | 1975-01-23 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Residual current circuit breaker |
DE2745464B1 (en) * | 1977-10-08 | 1979-01-25 | Felten & Guilleaume Carlswerk | Residual current circuit breaker |
-
1980
- 1980-08-21 AT AT0426180A patent/ATA426180A/en not_active Application Discontinuation
-
1981
- 1981-05-31 NL NL8102641A patent/NL8102641A/en not_active Application Discontinuation
- 1981-06-17 GB GB8118653A patent/GB2082408B/en not_active Expired
- 1981-07-08 ES ES503752A patent/ES8204223A1/en not_active Expired
- 1981-07-24 DE DE19813129277 patent/DE3129277A1/en active Granted
- 1981-08-13 IT IT49106/81A patent/IT1143408B/en active
- 1981-08-18 CH CH534081A patent/CH655411B/de unknown
- 1981-08-18 FR FR8115875A patent/FR2489038B1/en not_active Expired
- 1981-08-20 BE BE0/205723A patent/BE890026A/en not_active IP Right Cessation
- 1981-08-21 SE SE8104979A patent/SE447684B/en not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
FR2489038B1 (en) | 1985-10-25 |
ES503752A0 (en) | 1982-04-16 |
ATA426180A (en) | 1982-08-15 |
BE890026A (en) | 1981-12-16 |
CH655411B (en) | 1986-04-15 |
GB2082408A (en) | 1982-03-03 |
NL8102641A (en) | 1982-03-16 |
FR2489038A1 (en) | 1982-02-26 |
GB2082408B (en) | 1984-05-02 |
SE8104979L (en) | 1982-02-22 |
IT1143408B (en) | 1986-10-22 |
IT8149106A0 (en) | 1981-08-13 |
DE3129277A1 (en) | 1982-06-24 |
ES8204223A1 (en) | 1982-04-16 |
DE3129277C2 (en) | 1988-10-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3769548A (en) | Ground fault indicator | |
US6671150B2 (en) | Circuit breaker for detecting an excessive voltage and tripping responsive thereto | |
RU2481666C2 (en) | Automatic fault current shutdown device | |
US3611035A (en) | Ground fault protective system having grounded neutral protection | |
US4194231A (en) | Dual voltage ground fault protector | |
US5969921A (en) | Ground fault electrical switching apparatus for coordinating tripping with a downstream ground fault switch | |
SE447684B (en) | FELSTROMSSKYDDSOMKOPPLARE | |
EP2445074B1 (en) | A fault detecting device for electrical installations and equipment | |
EP3104482B1 (en) | A device for detecting a ground fault in an ac supply and load shedding disabled during self-test | |
GB2176069A (en) | A switch for protection against fault currents | |
CN107238749B (en) | Differential current sensor | |
RU2638299C2 (en) | Device for protection of windings of one-phase transformer from damages | |
US3505566A (en) | Ground relay system | |
US3676737A (en) | Ground-fault detector using square hysteresis loop reactor core | |
US3579280A (en) | Electrical ground fault detector with transformer coupling, a battery supply source and battery charging means | |
US3745415A (en) | Circuit breaker panelboard with grounded neutral protection | |
HU220493B1 (en) | Fault current protective switch | |
GB2251741A (en) | Rapid response ground fault circuit interrupter | |
ITMI982828A1 (en) | ELECTRONIC PILOTING CIRCUIT FOR BISTABLE ACTUATOR ACTIVATED BY PIEZOELECTRIC, PARTICULARLY FOR DEVICES | |
CN106340852B (en) | A kind of immersion protection against electric shock breaker | |
GB2074380A (en) | A fault current circuit breaker | |
EP1220410A2 (en) | An overvoltage protection accessory device for a residual current circuit breaker | |
US2820927A (en) | Anti-inrush sensing device | |
KR100483930B1 (en) | Inrush Current Fault Function Prevention Circuit for Over Load Breaker | |
KR200317444Y1 (en) | Inrush Current Fault Function Prevention Circuit for Over Load Breaker |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
NUG | Patent has lapsed |
Ref document number: 8104979-3 Effective date: 19900703 Format of ref document f/p: F |