Claims
- 1. A residual current device, comprising:a residual current tripping circuit which is independent of the main voltage and includes a core balance transformer; an overload tripping circuit which is supplied with the main current, wherein the residual current tripping circuit and the overload tripping circuit include a common tripping relay for operating a switching mechanism which switches a conductor network; and a power supply unit connected upstream of the overload tripping circuit and connected via a respective supply line to each conductor of the conductor network, the power supply unit being designed with a high impedance such that each supply line has a resistance of at least about 2.5 kΩ/V-times the magnitude of the main voltage in volts.
- 2. The residual current device as claimed in claim 1, wherein the overload tripping circuit comprises an evaluation circuit, which is connected to a temperature sensor. and is upstream of a threshold value circuit, for determining a load state.
- 3. The residual current device as claimed in claim 2, wherein the temperature sensor is arranged in the region of the core balance transformer.
- 4. The residual current device as claimed in claim 2, wherein the temperature sensor is a temperature-dependent non-reactive resistor.
- 5. The residual current device as claimed in claim 1, wherein the power supply unit includes a capacitor for storing the energy required to operate the tripping relay.
- 6. The residual current device as claimed in claim 5, wherein the overload tripping circuit is designed with a high impedance such that the current draw of the overload tripping circuit has an upper limit of about 80-90% of the quotient of 1/{square root over (3)}-times the main voltage and twice the resistance in each supply line where the current draw of the overload tripping circuit is less than or equal to F times the main voltage and F is a number between 0.8 and 0.9.
- 7. The residual current device as claimed in claim 1, wherein the power supply unit includes a capacitor for storing the energy required to operate the tripping relay.
- 8. The residual current device as claimed in claim 7, wherein the overload tripping circuit (I) is designed with a high impedance such that the current draw of the overload tripping circuit has an upper limit of about 80-90% of the quotient of 1/{square root over (3)}-times the mains voltage (U1/{square root over (3)}) and twice the resistance in each supply line where I≦(F*U1/{square root over (3)})/(2*R) and F is a number between 0.8 and 0.9.
Priority Claims (1)
Number |
Date |
Country |
Kind |
198 42 470 |
Sep 1998 |
DE |
|
Parent Case Info
This application claims priority to International Application No. PCT/DE99/02799 which was published in the German language on Mar. 23, 2000.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/DE99/02799 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO00/16459 |
3/23/2000 |
WO |
A |
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Number |
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Jun 1973 |
A |
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Oct 1980 |
A |
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Solleder et al. |
Oct 2001 |
B1 |
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Number |
Date |
Country |
29 38068 |
Oct 1987 |
DE |
0 495 771 |
Jul 1992 |
EP |
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Oct 1995 |
WO |
Non-Patent Literature Citations (1)
Entry |
Warum Fehlerstrom-Schutzschalter mit netzspannungsunabhangiger Auslosung, no date. |