Selection and installation of moulded case circuit breaker

First, the application place and selection principle of plastic-case circuit breaker:

1, high temperature places: ironmaking, casting, boiler room and other places, should be selected not affected by the temperature of pure electromagnetic (but not too high), the thermal - electromagnetic type temperature at 40 ° C ~ 60 ° C, should be reduced capacity use, the temperature above 60 ° C can not be used.

2, low temperature place: this refers to the place below -5 ° C, such as frozen warehouse, low greenhouse, ship open deck, etc., the temperature is too low will make the lubricant dry, and make the insulation brittle, so the user should order low temperature moulded case circuit breaker.

3, wet place: refers to the more humid places such as chemical plants, fish processing plants, etc., should be installed in the Waterproof Box, not in direct contact with water should be used wet hot belt plastic-case circuit breaker.

4, dusty places: such as cement factories, textile factories, the plastic-case circuit breaker can be loaded into the dust box for use.

5, coal mines and other mines: can choose 660 V voltage level of the plastic-case circuit breaker, and put the circuit breaker in the explosion-proof box.

6, ships: general civil transport ships, should be used with three (moisture-proof, mildew, salt spray) and resistance to a certain level of vibration, turbulence, tilt of the Marine plastic-case circuit breaker, the benchmark temperature is 45 ℃. Ships, in addition to the same as civilian ships (vibration, turbulence, tilt requirements are higher), but also require first-level impact resistance, the benchmark temperature is 50 ° C.

7, electric locomotive: similar to the ship, but not necessarily three defenses.

8, corrosive gas and salt spray places: such as chemical plants, pharmaceutical factories, petroleum refineries and other places, should use anti-corrosion plastic-case circuit breakers, and put them into waterproof boxes.

Second, the installation of plastic case circuit breaker:

All samples or instructions of moulded case circuit breakers at home and abroad will be installed vertically as its basic installation method.

Can it be mounted horizontally or horizontally? The test results show that there is almost no effect on overload protection when the thermodynamic-electromagnetic plastic-case circuit breaker is installed horizontally or horizontally, and the reaction spring (which is related to gravity) of the instantaneous release electromagnet has only 5% ~ 10% error in the test value.

The conclusion is that it can be installed horizontally or horizontally.

For the pure electromagnetic type that is hydraulic (oil cup type) molded case circuit breaker, its overload and short circuit protection with the same release, its overcurrent delay or instantaneous and the core center of gravity in the pipeline and the damping (delay) role of the silicone oil level has a great relationship, and these are related to the installation Angle. The test shows that the action value (current value) of 2 In should be increased by 20% in horizontal installation, reduced by 20% in inverse horizontal installation, and reduced by 12% in forward tilt of 45°. Therefore, the pure electromagnetic circuit breaker should be installed vertically, if it must be installed horizontally or horizontally, the current value should be determined according to the correction factor provided by the manufacturer's sample or information.