1. Types of accessories for molded case circuit breakers

　    two types: internal accessories and external accessories.

　　 In-machine accessories are auxiliary devices installed inside the molded case circuit breaker, including shunt release, under-voltage release, auxiliary switch and alarm switch. External accessories are accessories installed outside the molded case circuit breaker, including auxiliary handles, external operating handles, electric operating mechanisms, handle locking devices, mechanical interlocking devices, electrical interlocking devices, rear wiring devices, plug-in installations Stations and auxiliary contact devices, etc.

2. Accessories that indicate the status of molded case circuit breakers

The difference between  auxiliary switch and alarm switch is:

The auxiliary switch is mainly used to display the opening and closing status of the molded case circuit breaker. Through the opening and closing of the molded case circuit breaker, other related electrical appliances are controlled or interlocked. The alarm switch is mainly used when the molded case circuit breaker is disconnected due to a fault. Status display, timely implementation of control or interlocking to other related electrical appliances when the plastic case circuit breaker load fails.

3. Accessories to realize the undervoltage protection function of molded case circuit breakers

The undervoltage release is a protective accessory. When the power supply voltage drops to 35～70 of the rated voltage of the undervoltage release, the undervoltage release can trip the molded case circuit breaker; when the power supply voltage is lower than the undervoltage release When the rated voltage of the voltage release is 35, the undervoltage release can ensure that the molded case circuit breaker does not close; when the power supply voltage is higher than 85 of the rated voltage of the undervoltage release, the undervoltage release can ensure that the molded case opens The device is working normally.　　

4. Accessories for realizing the operation function of molded case circuit breaker

(1) The shunt release is an accessory that realizes the remote opening of the molded case circuit breaker. It is usually used for remote opening of the molded case circuit breaker in an emergency state and as a leakage relay and other protective electrical appliances. element.

(2) The electric operating mechanism is also an external accessory for remote operation of the molded case circuit breaker, which can be used to realize the remote opening operation of the molded case circuit breaker as well as the closing operation of the molded case circuit breaker.

(3) The auxiliary handle is generally used on large-capacity molded case circuit breakers of 600A and above for manual opening and closing operations.

(4) The external operating handle is an external accessory with the function of converting the up and down operation of the molded case circuit breaker into a rotary operation.

5. Accessories for realizing the locking and interlocking functions of molded case circuit breakers

(1) The handle locking device is a kind of protection that can make the operating handle of the molded case circuit breaker be reliably in the open or closed position (ie opening or closing lock), and does not affect the protection of the free tripping of the molded case circuit breaker mechanically Device.

(2) The mechanical interlocking device is also a kind of protection device, which is mainly used in the occasions where two plastic case circuit breakers cannot be energized at the same time in the dual power supply circuit.

(3) Electrical interlocking device (also called automatic power supply switching device) is a dual power supply protection device that automatically realizes switching.

6. Accessories for multiple installation and wiring methods of molded case circuit breakers

　　 In addition to the most common front-board wiring methods, there are also rear-board wiring methods and plug-in wiring methods for the installation and wiring of molded case circuit breakers.

(1) The wiring behind the board adopts the wiring device behind the board.

(2) The plug-in wiring method adopts the plug-in installation table.

7. Other

　　Auxiliary contact device is an accessory device specially designed for plug-in wiring with internal accessories.

　　Electric operating mechanism is not only an external accessory for remote operation of molded case circuit breakers, but also often used for on-site operation of switches above 630A (large switches are more laborious to operate manually).

　　The installation method and wiring method of molded case circuit breaker are not the same thing. According to the installation method, there are fixed (applicable to drawer cabinets), plug-in / withdrawable (applicable to fixed cabinets); according to the wiring method, whether fixed or plug-in / withdrawable, there are front-board wiring and back-board wiring. Some products have dedicated cables or busbar front/rear terminals.