The function of the latching electromagnet is not to close when there is no electricity, which is a mechanism that jams the closing button, and only the closing button can be pressed with electricity. It’s mainly used for preventing personnels from accidentally touching the closing circuit caused by accidents or the handcart is not in place to close the accident. Its interlock circuit can also form an electrical interlock with the disconnector switch, load switch.
The latching electromagnet is used in conjunction with the external circuit to prevent from closing circuit breaker in mistake (of course, it can also be used in disconnectors or load switches). In the circuit breaker closing circuit, the normally open auxiliary point is connected in series, and the closing circuit will be open only when the power is blocked. The top rod of the latching electromagnet is installed next to the closing shaft, and when it is not sucked up, the top rod will lock the closing mechanism, so that the circuit breaker cannot be manually closed. Therefore, when there is no electricity, it can prevent both electric and manual closing.
When the latching electromagnet in the circuit breaker (handcart) is in operation or when the secondary plug-in is not pulled out, there is always current through the electromagnet. The circuit breaker can close when the electromagnet close. Pull out the secondary plug-in, when the electromagnet is no power, the middle iron core falls to prevent the circuit breaker from closing. The function is to prevent the circuit breaker from closing when the secondary plug-in is pulled out.
There are two main types of blocking electromagnets:
1. Closing and locking electromagnet are used to lock and close. Only when the electromagnet is on power, the circuit breaker can be closed after the electromagnet closes. It’s usually used for interlock between circuit breakers. For example, adding such a latching electromagnet into a single-bus breaking system of two incoming circuit breakers will ensure that only one circuit breaker is put into operation.
2. The latching electromagnet of a circuit breaker handcart is to prevent the circuit breaker from being racked in or out by mistake. In the test position, only when the latching electromagnet is powered on, then the circuit breaker can be racked out.
Post time: Nov-09-2023