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Why Is The Main Contactor Coil Of Overhead Crane Suddenly Turned Off?

2018-06-12 15:39:27 Author:NUCLEON

In daily use of bridge cranes, it is often found that each interlock control switch works normally, but the main contactor coil suddenly loses power. And do you know which factors may influence that happens? After Nucleon crane's engineer analysis, the main cause of the disconnection of the main contactor coil of the overhead crane is as follows:

(1) The vibration occurring during the task of the cart causes the slippery rail and the guide rail to be loosely connected, and the power supply emerges. Therefore, the main contact of the main contactor and the normally open auxiliary contact are formed and disconnected at the same time, and the self-locking of the main contactor coil takes effect. Incur power cuts.

(2) The poor contact of the slide iron leads to a lack of phase when the single beam bridge crane reaches a certain section of the slide rail. If the missing phase happens to be connected to the line, the coil of the main contactor will be de-energized. Since the self-locking is effective, even if the overhead crane slides past the poor contact and regains power, the main contactor coil cannot be pulled by itself, and the start button must be renewed.

single beam bridge crane

(3) The vibration occurred during the lifting of the heavy object caused the main contactor to suck loosely, and the main contact and the normally open auxiliary contact were disconnected at the same time due to vibration, and the main contactor coil self-locking effected and the power was turned off.

In case of this situation, the main circuit and control circuit of the overhead crane will be de-energized. Because the bridge crane is still in operation, it cannot stop immediately, it is likely to hit a machine tool or other equipment, and more serious will result in casualties. So we should know the reasons and can deal with this problem in time.