XL power distribution cabinet XL power distribution cabinet "change our life"

XL power distribution cabinet

The low-voltage electrical appliances in the distribution cabinet are composed of fuses, AC contactors, residual current action protectors, capacitors and meters. These low-voltage appliances are designed and manufactured according to gb1497 basic standard for low voltage appliances, and their normal working conditions are specified accordingly: the upper limit of ambient air temperature shall not exceed 40 ℃; The average value of ambient air temperature in 24h shall not exceed 35 ℃; The lower limit of ambient air temperature shall not be lower than - 5 ℃ or - 25 ℃.

The distribution box transformed by rural power network operates outdoors. It is not only exposed to the direct sunlight to produce high temperature, but also generates heat during operation. Therefore, in the high-temperature season in midsummer, the temperature in the box will reach more than 60 ℃. At this time, the temperature greatly exceeds the specified ambient temperature of these electrical appliances, so the fault caused by overheating of electrical components in the distribution box will occur.

2. Faults caused by product quality

In the transformation of rural power network, due to the large number of required distribution cabinets and short construction period, the distribution box factory needed the supply time and quantity of low-voltage electrical appliances, resulting in the phenomenon that the requirements for product quality were not strict, resulting in the failure of some products shortly after they were put into operation. For example, some models of AC contactors cannot operate because the closing coil of the contactor is burnt out shortly after the distribution box is put into operation.

3. Faults caused by improper selection of electrical appliances in distribution cabinet

Due to the inappropriate selection of AC contactor capacity during manufacturing, AC contactors with the same capacity are installed for different outgoing circuits, and the imbalance of three-phase load is not considered, so the current level of some outgoing contactors cannot be increased by one current level based on the normal selection model, Therefore, the AC contactor is burnt out during operation in high temperature season in summer.