Contacts
Contacts are mechanically linked to the opening and closing mechanism of the circuit breaker's main circuit. They are primarily used to indicate the circuit breaker's open/closed status and are connected in the circuit breaker's control circuit to control or interlock related electrical components through the circuit breaker's opening and closing.
Trip Unit
A trip unit is a voltage-driven device whose voltage is independent of the main circuit voltage. A shunt trip unit is an accessory for remotely operating the circuit breaker. It can reliably disconnect the circuit breaker when the power supply voltage is equal to any voltage between 70% and 110% of the rated control power supply voltage.
Electric Operating Mechanism
This is an accessory used for remote automatic opening and closing of circuit breakers. There are two types of electric operating mechanisms: motor-operated and electromagnet-operated. Motor-operated mechanisms are used for molded case circuit breakers with a frame rating of 400A and above, and universal circuit breakers. Electromagnet-operated mechanisms are suitable for molded case circuit breakers with a frame rating of 225A and below. Whether using an electromagnet or a motor, their attraction and rotation directions are the same. Opening and closing are achieved solely by the position of the cam inside the electric operating mechanism. When operated by an electric mechanism, the circuit breaker should be able to reliably close at any voltage between 85% and 110% of the rated control voltage.
Energy-Release Electromagnet
This energy-release electromagnet is suitable for universal circuit breakers with a motor pre-energy storage mechanism (the electric energy storage mechanism stores energy in its operating spring mechanism). When the user presses the button, the electromagnet coil is energized, the electromagnet closes, releasing the energy storage spring, and the circuit breaker closes.
Rotary Operating Handle
Suitable for molded case circuit breakers. A mechanism for rotating the operating handle is installed on the circuit breaker cover. The handle's shaft is fitted into a mating hole in the mechanism, and the other end of the shaft passes through a door opening in the drawer cabinet. The handle is mounted on the exposed shaft end on the door of the assembly. The round or square base of the handle is fixed to the door with screws. This installation allows the operator to close or open the circuit breaker by rotating the handle clockwise or counterclockwise from outside the door.
Extended Handle
An external extended handle is directly mounted on the circuit breaker's handle. It is generally used on high-capacity circuit breakers of 600A and above for manual closing and opening operations.
Handle Locking Device
A locking device is installed on the handle frame, and a hole is drilled in the handle for locking with a padlock. It is mainly used to prevent others from opening the circuit breaker and causing a power outage when the circuit breaker is in the closed working state, or when the circuit on the load side of the circuit breaker needs maintenance or does not allow power to be supplied, so as to prevent someone from accidentally closing the circuit breaker, thereby protecting the safety of maintenance personnel or the reliable use of electrical equipment.
