GB2177560A - A fault-current protective switch for a c and d c fault currents without energy storage - Google Patents
A fault-current protective switch for a c and d c fault currents without energy storage Download PDFInfo
- Publication number
- GB2177560A GB2177560A GB08610625A GB8610625A GB2177560A GB 2177560 A GB2177560 A GB 2177560A GB 08610625 A GB08610625 A GB 08610625A GB 8610625 A GB8610625 A GB 8610625A GB 2177560 A GB2177560 A GB 2177560A
- Authority
- GB
- United Kingdom
- Prior art keywords
- fault
- switch
- electronic circuit
- tripping
- current
- 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.)
- Withdrawn
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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
- H02H3/26—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
-
- 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
- H02H3/05—Details with means for increasing reliability, e.g. redundancy arrangements
-
- 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
- H02H3/338—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 also responsive to wiring error, e.g. loss of neutral, break
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
A fault-current protection switch comprising a summating current transformer (10), to whose secondary winding (11) is connected the trip coil (26) both directly and also via an electronic circuit (13), so that both a.c. and d.c. fault currents, and a.c. fault currents with d.c. components can be detected and used for switching off a mains circuit.
Description
SPECIFICATION
Afault-current protective switch for a.c. and d.c. fault currents without energy storage
The invention relates to a fault-current protective switch.
The invention is particularly concerned with a switch comprising a contact device disposed in a suitable casing with terminals for the wiring cables and an associated switch latch, test device, and actuating means, a fault-currenttripping device with one ortwotripping coils, a cumulative current transformer, and an electronic circuit dependent on the mains voltage, the secondary winding ofthe cumulative currenttransformerbeing directly connected to the trippin coil of the fault-currenttripping device and thus the protective switch is triggered if alternating fault currents occur and, if required, also if pulsating directfaultcurrents, occur, and tripping is also brought about by the electronic circuit dependent on the mains voltage ifdirectfaultcurrents occur and, if required, also if alternatingfaultcurrentswith d.c. components occur, in thatthe d.c. ord.c.
component in the cumulative currenttransformeraltersthe voltage generated by an oscillator of the electronic circuit in a winding ofthetransformer,through asymmetry orthrough displacing the operating point, so that a switching operation is brought about via the electroniccircuitand uses the mains energy to actuate a fault-currenttripping device.
The stimulus towards the invention resulted from experience obtained in the use of such a fault-current protective c;rcuit, which has shown the need for new technical solutions in orderto close the gaps which have become known in the scope of this method of protection, which is now used in many countries.
The three possible basic circuits for constructing fault-current protective switches (known for short as Fl protective switches) were described 20 years ago (1). The circuits used as the auxiliary voltage source independent of the mains voltage are eitherthe secondary winding of the cumulative currenttransformer, which is directly connected to the fault-currenttripping device, orthe energy storage circuit - atrend-setting Austrian invention (Austrian Patent No. 197 468).
A modern fault-current prntective switch, however, must also control the tripping process in the event of fault currents occurring in the form of pulsating or smoothed d.c. currents. Of course it has always been known that Fl switches can be effective only against a.c. fault currents. If the fault current has d.c. components,the tripping sensitivity of the switch is disadvantageously influenced. Since increasing numbers of electronic components are being used in domestic appliances, the d.c. problem must also be solved. Itwas long thought that, if a short to earth occurred in the circuits used in practice in electric domestic appliances, the resulting fault current could occur only in the form of a pulsating d.c.In the case of fault currents of this kind, e.g. with half-wave rectification without a smoothing capacitor, it is possible to construct fau It-cu rrent protective switches independently ofthe mains voltage and using conventional circuits, i.e. including energy storage triggering (GB-B-2 082 408). However, itwas found impracticable to restrictthe manufacturers of electric appliances in the choice of electronic circuits, because ofthe Fl switch. Half-wave rectification with smoothing capacitors and three-phase rectification are particularly relevant in this connection.
Owing, however, to the transformertripping principle, circuits independent of the mains voltage cannot detect fault currents in the form of smoothed d.c. currents. In this case it is necessary to use electronic circuits which of course depend on the mains circuit and can process all forms of d.c. fault currents via cumulative currenttransformers. Circuits ofthis kind are described e.g. by US Patent3 768011 and DE-A-27 30874. The question therefore arises concerning the possible risks of using the mains as an auxiliary voltage supplyfor tripping fault-current protective switches.If the auxiliary voltage istaken onlyfrom an external conductor and the neutral conductor, the switch mayfail ifthe external conductor orthe neutral conductorfails (e.g. if fuse blows in the external conductoror if the neutral conductor breaks), and it will then be impossibleto detectfault currents resulting from shorts to earth of the othertwo external conductors. Even if all three external conductors of a three-phase network are used forthe auxiliary voltage supply, the neutral conductor may always break. In an attempt to remedy this situation, the Fl switch is tripped if the neutral conductor breaks (DE-A-28 25 881).If an additional connection, e.g. the earthed conductor, is usedforthis purpose, the resulting disadvantage is that the installation becomes more complicated and the earth potential is introduced into the switch. This makes the circuit more sensitiveto overvoltages, which occur mainly to earth. However,the main disadvantage oftripping in dependence on the mains voltage is that if faults to earth occur in the protected installation the auxiliary supply voltage will depend on the ratio between (a) the mains loop resistance between the transformer and the places where the auxiliary voltage supply is connected and (b) thetotal resistance ofthefault loop. This is shown in Figure 1 in the case of a faultto earth in an earthed installation.
If: ZL is the line impedance ofthe external conductorfromthetransformertothe Fl switch,
ZPEN is the line impedance ofthe PEN conductorfromthetransformertothe F switch, Z1 is the line impedance of the external conductorfrom behind the Fi switch to thefault, Z2 is the line impedance ofthe earthed conductorfromthe fault to the PEN conductor, UN isthe external conductor/PEN conductor mainsvoltage, and
Ua is the supply voltage of the electronic circuit dependent on the mainsvoltage,
the supply voltage will then be:
Iftherefore the fau Itto earth occurs near the place where the Fl switch is installed, the auxiliary voltage may become zero and tripping will be impossible.In such cases thefault to earth has to be eliminatedviathe anti-overcurrent devices and the Fl switch will be inoperative. Forthese reasons, in countries using switches with tripping systems dependent on mains voltage, the Fl switch provides only "additional protection" and appropriate restrictions are planned in international regulations (2,3).
It does not help if, as disclosed in DE-A-28 25 the neutral-conductor voltage is monitored relative to the earthed conductor. The reason isthatthe circuit fails if a short circuit occurs simultaneously with theshortto earth. In this case, as shown in Figure 1 the output terminals of the Fl switch are short-circuited togetherwith the earth conductor. The switch cannot trip, even thoughthe protected parts of the plant are receiving a fault voltage of e.g. 110 V.
This can be seen from Figure 1 where
ZL' = line impedance of external conductor from transformer to Fl switch,
ZN' = line impedance of neutral conductorfrom transformer to Fl switch,
ZL" = line impedance of external conductorfrom Fl switch to short-circuit, ZN" = line impedance of neutral conductor from Fl switch to short-circuit,
UN = external conductor/neutral conductor mains voltage, Ua = supply voltage of electronic circuit dependent on mains voltage PE = terminal for earthed conductor in Fl switch, Ik = short-circuit current It fault current
RA = earthing resistance of protected plant R5 = earthing resistance of neutral conductor in transformer station (system earth).
If thereforethe short circuit occurs nearthe Fl switch, the supply voltage disappears and the PEterminal also receives the short-circuit potential. It is quite impossible therefore for the switch to trip. The short-circuit lk flows through the external conductor and neutral conductor and the resulting voltage drop in the neutral conductor relative to the plant earth connection RAto thy system earth connection RB, becomes operative as the fault voltage. Owing however two the absence of the auxiliary voltage UA, the fault current le resulting from the fault voltage cannot trip the switch.In orderthereforeto use an Fl switch for protection against indirect contact (fault protection), the following conditions must be fulfilled:
1) The switch musttrip when the mains voltage supply is normal and a.c. or d.c. fault currents occur. If ittrips in the event of a.c. fault currents at the rated value lAn of the tripping fault current, it is sufficientfor physiological reasons (4) if tripping occurs at V2 x i,n for pulsating d.c. fault currents with half-wave rectification, 2 x lZ,n forfull-wave rectification, and 2.8 x lZ for a smoothed fault d.c. Electronic circuits dependent on the mains voltage are necessary for this purpose.Other auxiliary voltage sources such as batteriesareunsuitableforpractical reasons.
2) The switch must be tripped by a.c. fault currents even if the external conductor and/or neutral conductor fail and there is a simultaneous short-circuit and short to earth. In these cases the switch does not need to remain operative against d.c. fault currents, since the simultaneous occurrence of a mains fault and a d.c. fault current is a negligible safety risk and also because during short circuits the faultvoltage to earth remains below 120 V in mains up to 240 Vowing to the external conductor/neutral conductor voltage division, and consequently there is no overstepping of the conventional contact-voltage limit, which is 120 V for d.c.
As explained, circuits independent of the mains voltage cannot detect smoothed d.c., whereas constructions dependent on mains voltage fail if the external conductor and/or neutral conductor fail and if short-circuits occur simultaneously with faults to earth. The technical requirements regarding protection against indirect contact therefore exclude circuits independent ofthe mains voltage equally with circuits dependent on the mains voltage.
These apparently contradictory requirements on a switch giving protection against indirect contact (fault switch) have naturally resulted in new technical solutions. For example EP-A, based on Austrain patent application All 37/85, discloses a solution according to which the fault-current tripping device, preferably a permanent magnet, used for the energy storage circuit independent of mains voltage is also used fortripping via the electronic circuit independent of mains voltage.
Energy storage circuits have the advantage that they operate after a short delay and are therefore selective and insusceptibleto transient currents. This is a great advantage in protection against indirect contact. On the other hand, in the case of protection against direct contact, it is important to switch off as soon as possible and to keep the triggering current below 30 mA. Admittedly, tripping in the event of pulsating or smooth d.c. fault currents is unimportantfor additional protection, buttripping in the event of fault d.c. may still be required for special applications.
What is desired is a protective switch of the initially-mentioned kind which is inexpensive but of use against both d.c. and a.c. fault currents and against a.c. fault currents with d.c. fault-current components.
The present invention provides a fault-current protection switch as defined in claim 1.
Preferred features ofthe invention are disclosed in claims 2 etseq.
In this manner, the fault-currenttripping device is actuated via the electronic circuit and the tripping coil, using a.c. or d.c. and energy from the mains. The secondary winding ofthe cumulative currenttransformeris directly connected to the fault-currenttripping device and is used fortripping in the eventofa.c. or pulsating a.c. fault currents.
Use can be made of a tertiary winding for actuating the electronic circuit for detecting smooth fault currents and also fault currents with d.c. components. If the fault-currenttripping device has two partial tripping coils, the circuit for direct tripping can then be electrically isolated from the electronic circuit.
As is known, in the prior art, faulty tripping of protective switches by surge currents in thunderstorm discharges can be avoided if voltage-dependent resistors, e.g. anti-parallel connected diodes, are connected in parallel to tjie secondary winding ortertiarywinding ofthe cumulative current transformer. Voltage peaks are clipped as a result thus eliminating any impulsesfortripping thefault-currenttripping device. The winding flowed through by the oscillatorcurrentfrom the electronic circuit dependent on mains voltage can be used to make the protective switch insensitive to surge currents.To this end, as described above, voltage-dependent resistors may be connected in parallel to the aforementioned winding, thus ensuring insensitivity to surge currents and also protecting the electronic circuit from overvoltages,
The invention will be described further, by way of example, with reference to the accompanying drawings, in which:
Figures land 2are circuit diagrams of protective switches according to the prior art already discussed above; Figure 3 is a circuit diagram of one embodiment of a fault-current protective switch according to the invention; and
Figure 4 is a circuit diagram of another embodiment of a protective switch according to the invention.
The fault-current protective switch illustrated in Figure 3 comprising a cumulative currenttransformer 10 having primary windings formed bya neutral conductor and phase conductors L1, L2, and L3extending through the transformer 10. The secondary winding 11 ofthe transformer 10 is connected to a firsttripping coil (partial coil) 12 of a fault-currenttripping device 25 and trips the switch when a.c. or pulsating d.c. faultcurrents occur.
An electronic circuit 13 containing an oscillator is connected in parallel to the secondary winding 11. Leads 14,15 supplythe electronic circuit 13 with mains voltage from the phase conductor L1 and the neutral conductor N.Atthe outlet end, circuit 13 is connected to a second tripping coil (partial coil) 16 ofthe device 13.
The circuit 13 is for detecting d.c. fault currents or a.c. fault currents with d.c. components as follows. The cumulative current transformer 10 is premagnetizedviathe oscillator in the electronic circuit 13. If a d.c.fault current or an a.c. fault currentwith a d.c. components occurs, the operating point of thetransformeris displaced; this is detected by the circuit 13 and results in a signal being delivered to the coil 16, with the result thatthetripping device 25 trips a switch latch 17 which opens a contact device 18 in the phase conductors L1
L3 and neutral conductor N.In other words, if d.c. fault currents ora.c.fault currents with d.c. components occur, the voltage generated in the secondary winding 11 ofthetransformer 10 by the oscillator ofthe circuit 13 is changed through asymmetry orthrough displacement of the operating point so thatthetripping coil 16of the device 25 is energized via the electronic circuit 13, which is connected to the coil 16 in parallel with the secondary winding 11, energy from the mains also being usedforexcitation via lines 14and 15, and as a result the protective switch is triggered.A circuit 19 made up of two antiparallel-connected diodes and constituting a voltage-dependent resistor is provided parallel to the input of circuit 13 and consequently also parallel to the winding 1 1,thus giving protection againstovercurrents and surgevoltages.
Similarly, in the protective switch shown in Figure 4the secondary winding 11 ofthesinglecumulative currenttransformer loins directly connected to the first tripping coil 12, thus tripping the switch if a.c. or pulsating d.c. fault currents occur. In addition to the secondary winding 11 transformer 10 has atertiary winding 20 which is connected in parallel to the diode circuit 19 and the outputs ofwhich are connected to the electronic circuit 13. As before, the outputofthe circuit 13 is connected to thetripping coil 16 ofthe device 25.
As Figures 3 and 4show, the device 25 has two tripping coils 12 and 16, thetwo tripping circuits being electrically isolated from one another. As before, diode circuit 19 in Figure4 is for protection against surge currents and overvoltages and is connected in parallel to the oscillator current circuit in the output circuit ofthe tertiary winding 20. The switch latch 17 has an actuating knob 26 orT-handle 26forswitching the protective switch on or off.
References:
1) Beigelmeier, G: Modern protection againstfaultcurrents [in German], E.u.M. Volume 75(1958), part8, pages 157-164.
2) Beigelmeier, G: Thoughts on earthing (Tn-system) as the optimum protection against faults (protection against indirect contact) in electric installations [in German], OZE, Vol u me 37 (1984), part 12, page 483.
3) IEC 64 (Central Office) 151, January1985, lEC Pu bl Pubs. 364 Part 5, Chapter 53 Switchgearand control gear.
4) lEC-Report 479, second edition, Effects of electric shock of the human body, Part 2, Chapter 5.
Claims (9)
1. Afault-current protective switch comprising a contact device disposed in a casing with terminals for wiring cables and an associated switch latch, test device, and actuating means, a fault-current tripping device with a tripping coil, a cumulative current transformer, and an electronic circuit dependent on the mains voltage, the secondary winding of the cumulative current transformer being directly connected to thetrippin coil of the fault-current tripping device, whereby the protective switch is triggered if alternating fault currents occur and, if required, also if pulsating directfault currents occur, andtripping is also broughtabout bythe electronic circuit dependent on the mains voltage if directfault currents occur and, if required, also if alternating fault currents with d.c. components occur, in thatthe d.c. or d.c. component in the cumu lative currenttransformeralters the voltage generated by an oscillator of the electronic circuit in a winding of the transformer,through asymmetry orthrough displacing the operating point, so that a switching operation is brought about viva the electronic circuit and uses the mains energy to actuate a fault-current tripping device, characterised inthatthere is only one single cumulative current transformer and only one singlefault-current tripping device, both fortripping in dependence on the mains voltage by directly connecting the tripping coil to the secondarywinding ofthe cumulative currenttransformer, and also fortripping in dependence on the mains voltage, using the electronic circuit.
2. A protective switch as claimed in claim 1, in which the secondary winding of the cumulative current transformer is connected directly to the tripping coil and a tertiary winding of the transformer is connected to the tripping coil via an electronic circuit.
3. Aprotective switch as claimed in claim 1 or2, in which the tripping device has only onesingletripping coil, which is connected directly to the secondary winding of the cumulative currenttransformer.
4. A protective switch as claimed in claim 3 when dependent on claim 2, in which the tertiary winding ofthe cumulative currenttransformer is connected to the single tripping coil via the electronic circuit.
5. A protective switch as claimed in claim 2, in which the tripping coil comprises two partial coils, each designedforindependenttripping,the secondary winding being connected to one partial coil,thetertiary winding being connected to the other partial coil via the electronic circuit.
6. A protective switch as claimed in any preceding claim, in which voltage-dependent resistors are connected in parallel to the winding of the cumulative currenttransformerthrough which the oscillator current flows.
7. A protective switch as claimed in claim 6, in which the voltage-dependent resistors are antiparallel-connected diodes.
8. A protective switch as claimed in any preceding claim, in which the fault-cu rrent tripping device comprises a permanent magnet.
9. Afault-cu rrent protective switch substantially as described with reference to Figure 3 or Figure 4 of the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT130185 | 1985-05-02 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8610625D0 GB8610625D0 (en) | 1986-06-04 |
| GB2177560A true GB2177560A (en) | 1987-01-21 |
Family
ID=3510928
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08610625A Withdrawn GB2177560A (en) | 1985-05-02 | 1986-04-30 | A fault-current protective switch for a c and d c fault currents without energy storage |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0220215A1 (en) |
| AU (1) | AU5774586A (en) |
| ES (1) | ES8707384A1 (en) |
| GB (1) | GB2177560A (en) |
| GR (1) | GR860990B (en) |
| WO (1) | WO1986006563A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1701423B1 (en) * | 2005-03-03 | 2012-02-08 | Airbus Operations GmbH | Arrangement for improving the short circuit withstandability of an appliance by use of a bypass |
| DE102013105314A1 (en) * | 2013-05-23 | 2014-11-27 | Eaton Industries (Austria) Gmbh | Residual Current Device |
| DE102013105313A1 (en) * | 2013-05-23 | 2014-11-27 | Eaton Industries (Austria) Gmbh | Residual current circuit breaker (RC element) |
| GB2527892A (en) * | 2014-07-04 | 2016-01-06 | Siemens Ag | Residual current protection apparatus with detection which is purely dependent on the power supply system voltage. |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0349880A1 (en) * | 1988-07-07 | 1990-01-10 | Siemens Aktiengesellschaft | Fault current protection device |
| EP0522187A1 (en) * | 1991-07-08 | 1993-01-13 | Siemens Aktiengesellschaft | Ground fault circuit interrupter |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1808770A1 (en) * | 1968-11-14 | 1970-06-11 | Siemens Ag | Residual current circuit breaker |
| DE2348881C3 (en) * | 1973-09-28 | 1980-10-16 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Residual current circuit breaker |
| DE2555302C3 (en) * | 1975-12-09 | 1982-02-25 | Brown, Boveri & Cie Ag, 6800 Mannheim | Residual current protection circuit |
| LU78992A1 (en) * | 1978-02-02 | 1979-09-06 | N Gath | FAULT CIRCUIT BREAKER |
| FR2430680A1 (en) * | 1978-07-05 | 1980-02-01 | Saparel | AC or DC fault current detector - operates by sensing inductance change in transformer with toroidal core |
-
1986
- 1986-04-12 EP EP19860902330 patent/EP0220215A1/en not_active Withdrawn
- 1986-04-12 AU AU57745/86A patent/AU5774586A/en not_active Abandoned
- 1986-04-12 WO PCT/DE1986/000162 patent/WO1986006563A1/en unknown
- 1986-04-15 GR GR860990A patent/GR860990B/en unknown
- 1986-04-26 ES ES554413A patent/ES8707384A1/en not_active Expired
- 1986-04-30 GB GB08610625A patent/GB2177560A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1701423B1 (en) * | 2005-03-03 | 2012-02-08 | Airbus Operations GmbH | Arrangement for improving the short circuit withstandability of an appliance by use of a bypass |
| DE102013105314A1 (en) * | 2013-05-23 | 2014-11-27 | Eaton Industries (Austria) Gmbh | Residual Current Device |
| DE102013105313A1 (en) * | 2013-05-23 | 2014-11-27 | Eaton Industries (Austria) Gmbh | Residual current circuit breaker (RC element) |
| GB2527892A (en) * | 2014-07-04 | 2016-01-06 | Siemens Ag | Residual current protection apparatus with detection which is purely dependent on the power supply system voltage. |
| GB2527892B (en) * | 2014-07-04 | 2021-09-08 | Siemens Ag | Residual current protection apparatus with detection which is purely dependent on the power supply system voltage. |
Also Published As
| Publication number | Publication date |
|---|---|
| AU5774586A (en) | 1986-11-18 |
| GB8610625D0 (en) | 1986-06-04 |
| ES8707384A1 (en) | 1987-07-16 |
| EP0220215A1 (en) | 1987-05-06 |
| ES554413A0 (en) | 1987-07-16 |
| GR860990B (en) | 1986-07-21 |
| WO1986006563A1 (en) | 1986-11-06 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |