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Magnetic circuit breakers make use of field strength of magnetic coils to trip a latch that will then open up contacts of circuit breaker. This method is used for high current faults, like in a short circuit. This method is designed to trip instantly.
A thermal-magnetic circuit breaker incorporates both a thermal strip and a magnetic coil. This type of circuit breaker is able to protect against momentary overloads as well as high or short circuit current faults.
What happens if circuit breaker is placed in a high temperature environment? The thermal bimetallic strip bends on high temperature. In this case, current is not causing high temperature in bimetallic strip, but ambient air is! The current may still be below safe operating rated value for motor.
In this case, a compensating bimetallic strip may be incorporated into circuit breaker to eliminate this type of error. These circuit breakers are often used in hot areas like furnace, oven, and boiler rooms.
Circuit breakers can be reset very quickly, once they have tripped. Can your break or vacation be reset very quickly too? Don't reset. Take a long break!
Until next time...
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