As can be seen from the name, the difference between them is that when the temperature threshold is not reached, one of their contacts is in a disconnected state, and the other is always in a closed state.

1、Normally open temperature switch, for example, he will operate when the temperature is 50 degrees, then, when the temperature is below 50 degrees, the normally open temperature switch is always off state.

2、When the temperature exceeds 50 degrees, then the normally open contact will be closed, if applied in the circuit, there will be a loop connected to the normally open contact, forming a conduction state.

For example, as a temperature indicator, when the temperature reaches 50 degrees, the normally open contact closure loop is in the channel state, then the indicator light will be lit, and we know that 50 degrees has been reached.

3、Similarly, normally closed temperature switches, such as in many electric water heaters, will be used in the circuit, for example, there are some kettles at the bottom of the pot, there will be some temperature protection normally closed switches.

4、When the temperature is greater than 100 degrees, the temperature switch of the intestinal wall is disconnected, so that the entire kettle plays a protective role against dry burning.