Scope of Application
Miniature circuit breakers are suitable for AC 50Hz or 60Hz circuits with a rated operating voltage of AC230V/400V and a rated current up to 80A. They provide overload and short-circuit protection for the circuits and can also be used for infrequent switching operations. These circuit breakers are suitable for commercial office buildings, residential buildings, and similar structures. This product conforms to GB/T10963.1 and IEC60898-1 standards and is at an internationally advanced level.
Product Features
3.1 High rated breaking capacity, up to 10kA; 3.2 During normal operation, the contacts can only remain in the closed or open position; 3.3 Post-type terminals for easy installation.
Main Structure
The circuit breaker mainly consists of an insulating shell, operating mechanism, time-delay and instantaneous trip unit, contacts, and arc-extinguishing chamber. The operating mechanism is a free-tripping mechanism. During normal or abnormal operation, the contacts can only remain in the closed or open position. The moving contacts of the multi-pole circuit breaker are mechanically linked, with each pole closing or opening essentially simultaneously.
Working Principle
When the handle is pushed to the ON position, it instantly closes the contacts when the handle reaches a certain angle, eliminating the influence of operation on the contact closing speed. When an overload fault occurs, the overload current bends the bimetallic strip, pushing the latch to trip. The mechanism then causes the contacts to quickly disconnect, cutting off the circuit. When a short-circuit fault occurs, the short-circuit current passes through the coil, attracting the electromagnet. The lever pushes the latch open, causing it to trip and achieving the function of cutting off the circuit. The circuit breaker has a current-limiting function. During a short circuit, the iron core causes the push rod to open the contacts and simultaneously open the latch. The arc resistance reduces the short-circuit current, thus limiting the current. The mechanism operates simultaneously, keeping the contacts in the open position. The arc is quickly extinguished through the combined action of the arc-extinguishing system.
