When the end users operate the appliances, the working current might exceed the rated value. If so, what would happen to the bimetallic thermal switch? There are some possible results:
1. The thermal switch would trip off earlier than the rated temperature. The reason is that the bigger current would generate more heat, and the bimetal would sense higher temperature than the rated value. So, it would trip off earlier.
2. The life endurance would be shorter. Bigger current would hurt both bimetal and contacts. There would be flash over between two contacts. If the current is too big, for example, 3 or 4 times of rated value, the two contacts would be stuck and could not open. That would make thermal switch malfunction, or even cause fire.
3. The thermal switch failed to action in few seconds and even burned the insulation sleeving
Therefore, it is very important for the user to operate the thermal switch correctly and try to avoid overloading the thermal switch.