Circuit breaker in the influence of environment temperature
Circuit breaker is the most widely used in the power distribution system, one of the most amount of electrical power distribution. Customers use the cares generally is, different types of circuit breaker used in different places, conditions should be how to drop. For example circuit breaker installed in the electrical equipment ( switch cabinets, boxes), as a result of a variety of electrical appliances ( knife switch ( or switch ), contactor, breaker, a connecting copper bar etc. ). The need to consider the issue, one is the environmental temperature on the circuit breaker characteristics author.
Universal type circuit breaker
1) air circuit breaker, such as DW15-630 have thermal electromagnetic type ( using thermal relay as a long-time delay overload protection, electromagnetic tripping device for short-circuit instantaneous protection ), the capacity reduction and plastic shell type thermal electromagnetic consistent. Other universal type circuit breaker, such as DW45 ACB is so.
2) electronic tripping device ( including a microprocessor trip )
Electronic and microprocessor release more used in universal type ( frame type ) in the circuit breaker, the larger current specifications of the plastic shell type circuit breaker, breaker is used in industrial electronic components, to adapt to the environment temperature range is broad (- 40-85 ), namely in this temperature range, electronic components of the performance will not be change. Analysis of reasons: changes in ambient temperature, the electronic elements on the properties of no effect. In the current specifications should be derated because copper wiring in the high current heating induced by the overall temperature rise rise. The low voltage electrical, environmental temperature in 10-40 circuit breaker temperature rise basically has no effect, while more than 40 are affected, a lesser extent.
Plastic casing type circuit breaker
From the present domestic and foreign market sales of large plastic shell type circuit breaker, a full electromagnetic type ( commonly known as the cup type release ), an electromagnetic tripping device type thermal and electronic tripping device and a tripping device types.
1) electromagnetic cup tripping device is used for overload long-time delay, and for short circuit current of instantaneous protection (i.e., overload and short circuit protection for use with an oil cup trip). Long time delay overload protection delay, on the reverse force spring in the oil cup and methyl silicone oil to damp the floating core upward ( instantaneous when the oil cup floating core under large current, do not have to rise to release the armature under suction, to trip the circuit breaker ).
2) with the largest number of is thermal electromagnetic type. Its long-time delay overload by using thermal bimetal element, short circuit current of instantaneous adopts an electromagnet system. Different manufacturers, in the provision of manual or sample of circuit breaker capacity reduction using the current and environmental temperature relationships between tables, or by the temperature and the current curve representation, called temperature compensation curve.
3) for household or similar circuit breakers for overcurrent protection ( typical products are DZ47-63, C45N Tianjin MGE ). Circuit breaker with standard is GB10963, and 1), 2) class (GB14048.2) is a different reference calibration temperature is 30 degrees, ( of course, as the protection of domestic appliances, its long-time delay overload and short circuit instantaneous protection characteristic is not the same).
The information above in electrical switch factory provide for reference www.jiandq.com