Magnetic Contactor

Our machine is run with control switches with MAGNETIC CONTACTORS or magnetic starters (CHINT brand). These are necessary to run the electric motors of our block machine. A current goes through the contactor, and its electromagnet pulls back its moving contacts and brings it together with the fixed contacts to rapidly send a large amount of current to the electric motors.

These contactors are designed to be robust especially with our machine where some of the motors run at least 100 cycles each day. So, imagine a light switch that you flick a hundred times a day, but in this case it doesn't just switch the light on, but the switch itself is involved in a complex mechanism. 

The Sassin Contactor replacement that also burned up

One of our contactors seemed to be replaced much earlier than the others. It seemed odd that the electrical guy who first installed this used a "smaller capacity" contactor, when in fact the motor it operates is one of the larger ones. The damaged contactor was immediately replaced at first with a similar capacity contactor from a different brand - Sassin (though both Sassin and Chint are made in China), but after a week, the same thing happened. We decided to get a larger capacity of the same Sassin brand, and so far its been months since any problems arose.We are however tempted to try our some German brands, but costs of these are prohibitive.

The larger capacity contactor

But obviously, the best advice we can give is to consult your electrical engineers to determine the correct ratings of your electrical components. This would avoid further damage, and potential harm to the workers.