There is a fuse, why should the thermal relay
Thermal relay acts as a control current
Thermal relay function:
The role of thermal relay is the motor overload automatically cut off the power supply, thermal relay structure is two pieces of expansion coefficient of different metal sheet composition, the current is too large when the expansion coefficient of the first expansion, play a role in cutting off the power. Thermal relay after manual reset and automatic reset.
Fuse function:
When the circuit fails or abnormal, accompanied by rising current, and the rising current may damage some important devices in the circuit or expensive devices, it is possible to burn the circuit or even cause a fire. If the circuit is correctly placed in the fuse, then the fuse will rise in the current to a certain height and a certain time, their own fuse cut off the current, which play a protective circuit safe operation
Fuses and thermal relays can play the role of "overload protection".
Once the fuse in the fuse is selected, the performance of the overload is fixed. The thermal relay set the temperature can be adjusted, more convenient.
Thermal relay function is to control the temperature, when the machine temperature rises to the thermal relay set the temperature limit, the automatic circuit breaker circuit breaker
Fuse is to control the current, the machine load is greater than the rated value, the current will be too large, the fuse is broken and protected
You may not really understand the place where the current is too large will produce heat, but the location is not the same installed ah
One is the body of the temperature control, one is the circuit control
