Apparatus and method of preventing malfunction of circuit breaker in metal-clad and metal enclosed switchgear
AssigneeKepco Engineering & Construction Company, Inc.
InventorCheoungjoon LEE
Life of this patent
Estimating the term…
Abstract
According to an embodiment of the present disclosure, an apparatus of preventing a malfunction of a circuit breaker may include a circuit breaker and a variable resistor installed on a distributing board, the variable resistor being disposed outside the circuit breaker separately from the circuit breaker, wherein the variable resistor is connected in parallel to an anti-pumping auxiliary relay RW, and total resistance of the anti-pumping auxiliary relay RW and the variable resistor connected in parallel to each other is less than resistance of the anti-pumping auxiliary relay RW.
Claims7
An apparatus of preventing a malfunction of a circuit breaker, comprising:
- a first Man-Machine Interface System (MMIS) including an MMIS closing coil monitoring relay RCM;
- a second MMIS including an MMIS trip coil monitoring relay RTM;
- a circuit breaker including a breaker closing coil relay RCC, a breaker trip coil relay RTC, and an anti-pumping auxiliary relay RW;
- and
- a resistance adjustment unit installed on a distributing board, and configured as a variable resistor connected in parallel to the anti-pumping auxiliary relay RW in the circuit breaker,
- wherein the anti-pumping auxiliary relay RW is configured to perform anti-pumping when the circuit breaker is closed.
An apparatus of preventing a malfunction of a circuit breaker, comprising a circuit breaker and a variable resistor respectively installed on a distributing board, the variable resistor being disposed outside the circuit breaker separately from the circuit breaker,
- wherein the circuit breaker comprises:
- a breaker closing coil relay RCC;
- a breaker trip coil relay RTC;
- and
- an anti-pumping auxiliary relay RW configured to perform anti-pumping when the circuit breaker is closed,
- wherein the variable resistor is connected in parallel to the anti-pumping auxiliary relay RW, and total resistance of the variable resistor and the anti-pumping auxiliary relay RW connected in parallel to each other is less than resistance of the anti-pumping auxiliary relay RW.
A method of detecting a malfunction of a circuit breaker, comprising:
- connecting a variable resistor installed on a distributing board together with an anti-pumping auxiliary relay RW in a circuit breaker in parallel to the anti-pumping auxiliary relay RW to reduce total resistance;
- causing current to flow continuously to the breaker closing coil relay RCCinstalled in the circuit breaker and connected in series to a Man-Machine Interface System (MMIS) closing coil monitoring relay RCM included in a first MMIS, and causing current to flow continuously to the breaker trip coil relay RTC installed in the circuit breaker and connected in series to an MMIS trip coil monitoring relay RTM included in a second MMIS;
- and
- providing a notice when the MMIS closing coil monitoring relay RCM and the MMIS trip coil monitoring relay RTM detect a circuit disconnection.
Dependencies are inferred from the claim text.