A method is disclosed for testing a latching solenoid of a switch and a testing device for carrying out the method is disclosed. The switch includes a switching contact, formed by contact elements mechanically separated from one another when the switching contact is open; an electronic trip unit, to respectively monitor the current passing via the contact elements and test whether a current-dependent tripping condition is satisfied; and an actuator, to separate contact elements after actuation, the trip unit actuating the actuator via the latching solenoid when the tripping condition is satisfied; and an electrical energy store, to charge to a voltage before the tripping and to be discharged via the latching solenoid. After a period of time after the tripping, the voltage of the energy store is compared with a reference value and a fault signal is output if the voltage of the energy store is above the reference.

A method is disclosed for testing a latching solenoid of a switch and a testing device for carrying out the method is disclosed. The switch includes a switching contact, formed by contact elements mechanically separated from one another when the switching contact is open; an electronic trip unit, to respectively monitor the current passing via the contact elements and test whether a current-dependent tripping condition is satisfied; and an actuator, to separate contact elements after actuation, the trip unit actuating the actuator via the latching solenoid when the tripping condition is satisfied; and an electrical energy store, to charge to a voltage before the tripping and to be discharged via the latching solenoid. After a period of time after the tripping, the voltage of the energy store is compared with a reference value and a fault signal is output if the voltage of the energy store is above the reference.

A lockout subassembly of an electronic circuit breaker. The lockout subassembly includes a rotatable latch bar having an engagement portion configured to engage with and prevent movement of an operating handle to an ON position, the rotatable latch bar including a lock portion, and a latch device configured to be receivable in the lock portion, wherein rotation of the rotatable latch bar is limited between a first and second rotational position in response to the latch device being received in the lock portion. The lockout of the operating handle can be removed upon passing at least one test so that the operating handle can be moved to the ON position. Circuit breakers including the lockout subassembly and methods of operating the circuit breaker are provided, as are other aspects.

Provided is a black box apparatus for analyzing a cause of arc interruption including: a controller which is installed on a power supply line and receives data detected from a CT detecting a current, a ZCT detecting a short circuit, and a voltage detector detecting a voltage; and an interruption unit which interrupts a power supply by receive a signal from the controller to operate a switch, in which the controller includes a calculation unit calculating data detected from the CT, the ZCT, and the voltage detector; a determination unit determining whether the arc occurs using the result of the calculation unit; and a storage unit storing data up to a predetermined time before the operation when the interruption unit operates to interrupt the power supply. Therefore, it is possible to accurately analyze reproduction for preventing occurrence of electrical fires and a cause of the arc interruption and determine an unstable condition of a power supply device which instantaneously occurs.

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 R.sub.W, and total resistance of the anti-pumping auxiliary relay R.sub.W and the variable resistor connected in parallel to each other is less than resistance of the anti-pumping auxiliary relay R.sub.W.

The present method relates to a method for checking a multi-pole electrical circuit breaker. The multi-pole electrical circuit breaker comprises a plurality of poles (101-103). Each of the plurality of poles (101-103) comprises a first connection (121-123) and a second connection (131-133). Closing the particular pole (101-103) makes it possible to electrically connect the first connection (121-123) of the particular pole (101-103) to the second connection (131-133) of the particular pole (101-103) via the pole. In the method, a plurality of micro-ohm measurements are carried out at the plurality of poles (101-103), while the plurality of poles (101-103) are earthed on both sides in a P-P-P-E configuration. A contact resistance of one of the plurality of poles (101-103) is determined on the basis of the plurality of micro-ohm measurements.

An energy storage apparatus 50 includes: a cell 62; positive and negative external terminals 51, 52; a current interruption device 53 disposed on a first line 55P that connects the cell and one of the external terminals; a resistor 54 for current measurement that is disposed on a second line 55N that connects the cell and the other of the external terminals; a discharge circuit 120 connected to the cell 62 and the current interruption device 53 in parallel; and a control device 130. The discharge circuit 120 includes a discharge resistor 121 and a discharge switch 123. The control device 130, in a state where the current interruption device 53 is controlled to take an open state, measures currents I1, I2 by the resistor 54 with respect to a state where the discharge switch 123 is in a closed position and a state where the discharge switch 123 is in an open position, and diagnoses a failure in the current interruption device 53 based on a difference ?I between a current value I2 measured when the discharge switch 123 is in the closed position and a current value I1 measured when the discharge switch 123 is in the open position.

A switchgear system includes a switchgear frame and a truck carrying a circuit breaker, which includes a breaker housing, a fixed electrical contact and a movable electrical contact mounted within the breaker housing, an actuator piston connected to the movable electrical contact, and a drive assembly coupled to the actuator piston. A sensor circuit is mounted on the switchgear frame under the truck and aligned with the circuit breaker and configured to acquire displacement data of the actuator piston when in a contact testing position. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

A switchgear system includes a switchgear frame and a truck carrying a circuit breaker, which includes a breaker housing, a fixed electrical contact and a movable electrical contact mounted within the breaker housing, an actuator piston connected to the movable electrical contact, and a drive assembly coupled to the actuator piston. A sensor circuit is mounted on the switchgear frame under the truck and aligned with the circuit breaker and configured to acquire displacement data of the actuator piston when in a contact testing position. A controller is coupled to the sensor circuit and configured to receive the displacement data and determine electrical contact erosion within the circuit breaker.

Resistance values for a first time for respective areas of a plurality of electrical connections are generated. Respective normalized resistance values are generated from the resistance values. Respective temperature rise values for a second time for respective ones of the areas of the electrical connections are generated. An average temperature value is generated from the temperature rise values. Respective normalized temperature rise values for the generated temperature rise values are generated based on the average temperature values. An abnormal condition of at least one of the connections is detected responsive to the normalized temperature rise values and the normalized resistance values.