Indicator lights: Most of them are LEDs, which have long life, short life such as bubbles and bulbs, and AC and DC voltages.

Buttons and emergency stop switches: buttons are often used for pneumatic, tentative control buttons, and some rotary buttons; emergency stop buttons are generally red and yellow.

Fuse: Mainly a protection circuit that can blow the protection circuit when the voltage and current are too large.

Transfer switch and power switch: control button.

Circuit breaker: It is mainly to restore the short circuit protection. When the circuit and the electrical device are instantaneously short-circuited and instantaneously high-current, the device automatically trips to protect the rear circuit.

AC contactor: It is mainly used to control the on/off of the equipment of the main circuit. Generally, the current is large. The contact is used to control the power supply.

Intermediate relay: It acts as a protection circuit as well as the AC contactor.

Thermal relay: It is a thermal sensing component, mainly used for protection of equipment over temperature, and automatic short circuit protection.

Delay protector: Generally divided into power-on delay and power-off delay.

Knife switch: Mainly from manual power off control and control, generally divided into 2 and 3 knives.

Leakage switch: mainly used to protect personal safety, there are single-phase and three-phase leakage switch.