Low voltage circuit breaker installation precautions

The correct installation of the low-voltage circuit breaker directly affects its performance and safety. Generally pay attention to the following issues:

(1) Before installation, check whether the technical parameters listed on the nameplate of the low-voltage circuit breaker meet the requirements for use.

(2) The low-voltage circuit breaker should be installed vertically. The low-voltage circuit breaker wired in front of the board can be installed on the metal bracket or the metal base plate, but the low-voltage circuit breaker connected behind the board must be installed on the insulating base plate. The bracket or bottom plate of the fixed low-voltage circuit breaker must be flat to prevent damage to the insulating base when the screws are tightened. In order to prevent accidents caused by arcing, the copper busbar of the low-voltage circuit breaker should be packed with 200mm insulation or phase-interval arc plate from the insulation base.

(3) The power supply should be connected to the incoming terminal of the static contact of the low voltage circuit breaker, and the trip end should be connected to the load. In order to ensure the protection characteristics of the overcurrent release, the cross section of the connecting wire should be selected according to the rated current of the trip unit.

(4) When the circuit breaker is used with the fuse, the fuse should be installed before the circuit breaker to ensure safe use.

(5) The thermal release and electromagnetic release of the low-voltage circuit breaker have been calibrated and sealed with red paint before leaving the factory. They must not be adjusted by themselves during installation to avoid affecting the action characteristics of the release. If the working current of the place of use does not match the rated working current of the trip unit, the low-voltage circuit breaker suitable for the rated working current of the trip unit shall be exchanged.

(6) In order to prevent arcing, the arcing distance of the circuit breaker should be taken into consideration during installation, and it is noted that the busbar is not connected to the arcing distance above the arc extinguishing chamber.

(7) When the low-voltage circuit breaker is used as the control switch of the main circuit breaker or the motor, an isolating switch, a knife switch or a fuse must be installed on the power supply line side of the circuit breaker as an obvious breaking point. Products with grounding screws should be reliably grounded.

(8) If the low-voltage circuit breaker uses the electric operating mechanism, it must pay attention to the power supply voltage of the operating mechanism, and it cannot be connected incorrectly.

(9) The low-voltage circuit breaker should remove the internal dust before installation, and add some lubricating oil to each transmission part properly; wipe the anti-rust grease on the working surface of the electromagnet of the release unit to avoid affecting the action value of the electromagnetic mechanism.