Accessories for molded case circuit breakers (MCCBs) (hence referred to as circuit breakers) give more control ways to circuit breakers and also extend the protection capabilities as a derivative and complement to their purposes. As such, it has evolved into a necessary and vital component of circuit breakers.
UEM5Z3 Intelligent MCCB Circuit Breaker
Types of circuit breaker accessories
It falls into two groups: internal and outside accessories.
Undervoltage release, shunt release, auxiliary switch and warning switch are among the internal accessories placed inside the circuit breaker. Auxiliary handle, external operating handle, electric operating mechanism, handle locking device, mechanical interlocking device, electrical interlocking device, rear wiring device, plug-in mounting platform and auxiliary contact device, etc. are among external accessories installed outside the circuit breaker.
Accessories that indicate the status of the circuit breaker
Whereas the alarm switch is mostly used to control or interlock other associated electrical appliances through the opening and closing of the circuit breaker, the auxiliary switch is mostly used to show the opening and closing state of the circuit breaker. Mostly used to show the status when the circuit breaker is unplugged due to a defect and to quickly regulate or interlock other linked electrical appliances when the circuit breaker load fails is the alarm switch.
Accessories that implement the undervoltage protection function of the circuit breaker
One such a protective accessory is the undervoltage release. Undervoltage release can trip the circuit breaker when the power supply voltage falls to 35% to 70% of the rated voltage of the undervoltage release; undervoltage release can ensure that the circuit breaker is not closed when the power supply voltage is lower than 35% of the rated voltage of the undervoltage release; undervoltage release can ensure the normal operation of the circuit breaker when the power supply voltage is higher than 85% of the rated voltage of the undervoltage release.
Accessories for realizing circuit breaker operation functions
(1) Shunt release is an accessory for realizing remote opening of circuit breaker. It is usually used for remote opening of circuit breaker in emergency and as an actuator for protection devices such as leakage relay.
(2) Electric operating mechanism is also an external accessory for remote operation of circuit breaker. It can be utilized to implement circuit breaker remote opening and closing.
(3) Auxiliary handle is generally used for large-capacity circuit breakers of 600A and above for manual opening and closing operations.
(4) External operating handle is an external accessory with the function of converting the up and down operation of circuit breaker into rotation operation.
Accessories for realizing circuit breaker locking function and interlocking function
(1) Handle locking device is a protective device that can make the circuit breaker operating handle reliably in the open or closed position (i.e. opening or closing lock) without affecting the free tripping of circuit breaker mechanically.
(2) Mechanical interlocking device is also a kind of protection device, which is mainly used in the case where two circuit breakers in the dual power supply circuit cannot be powered on at the same time.
(3) Electrical interlocking device (also called automatic power switching device) is a dual power protection device that automatically switches.
Accessories for achieving several circuit breaker installation and wiring techniques
Apart from the most often used front panel wiring technique, the installation and wiring techniques of circuit breakers also include rear panel wiring method and plug-in wiring method.
(1) The rear panel wiring method uses the rear panel wiring device.
(2) The plug-in wiring method uses the plug-in installation table.
UEM5 AC MCCB Circuit Breaker
Others
The auxiliary contact device is an accessory device specially matched with the plug-in wiring method with internal accessories.
Apart from being an external accessory for remote operation of circuit breakers, the electric operating mechanism is widely utilized for on-site operation of switches above 630A (manual operation of such switches is more arduous). Molded case circuit breakers have different wiring and installation techniques than one another.
The installation method specifies fixed type (suitable for drawer cabinets) and plug-in/withdrawable type (suitable for fixed cabinets); the wiring method specifies front-board wiring and rear-board wiring for both fixed and plug-in/withdrawable types; some products have special front/rear wiring terminals for cables or busbars.
Post time: 7 月-18-2024