On-off control is the simplest form of temperature control. All temperature controllers use a setpoint, which establishes the temperature at which a process is maintained.

On/off temperature control does not provide very accurate control, but it may be the only choice given the type or class of controlled device/equipment. Therefore, it still is an important ingredient ...

Fuses and thermistors can be integrated directly into the heating elements to provide additional over-temperature protection as well as closed-loop feedback control.