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Classification and working conditions of DC circuit breakers
The DC circuit breaker mainly consists of the neutral bus circuit breaker (NBS), the neutral bus grounding circuit breaker (NBGS), the metal circuit breaker (MRTB), and the earth return circuit breaker (ERTB).
1, the installation site altitude is not more than 2000m;
2, the ambient air temperature is not higher than +40 is not lower than -5, and the average value of 24 hours is not more than +35 (except for special order)
3, the installation location of the air relative humidity. The highest temperature of +40, no more than 50[%], at a lower temperature can be allowed to have a higher relative humidity, such as 2O 90[%]. Take special measures to be occasionally generated by dry temperature changes.
4, in the air in the air without an explosion hazard of the medium and the metal and the destruction of the insulation of the insulation of gas and electricity.
5, no rain and snow.
6, pollution level is 3.