Distribution box fault solution

When the distribution box is running, it is inevitable that there will be failures. For some common faults, some improvements can be made to the distribution box.

1. If the power distribution platform on the column is added, when making the shell of the distribution box, a stainless steel plate with a thickness of 2mm can be selected, and the size of the distribution box shall be appropriately enlarged in proportion to increase the distance between the outgoing lines of each branch, the outgoing line and the box. The electrical safety distance of the housing. This is conducive to the operation and maintenance of agricultural electricians and the replacement of fused parts, and it can also dissipate heat.

2. Selection of residual current action protector. Products that meet the GB6829 standard and have been certified by the China Electrical Product Certification Committee must be selected. A power-saving and low-sensitivity time-delay protector similar to the LJM (J) series can be selected.

3. A protection circuit is used to prevent the occurrence of external circuit failures powered by the distribution box. Choose an intelligent phase loss protector with a smaller volume, such as the DA88CM-II motor phase loss protection module, which is installed in the distribution box to prevent the motor from burning out due to low-voltage phase loss operation.

4. Selection of fuses. The rated current of the total overcurrent protection fuse on the low-voltage side of the distribution transformer should be greater than the rated current of the low-voltage side of the distribution transformer. Generally, 1.5 times the rated current is taken. The rated current of the melt should be determined according to the allowable overload multiple of the transformer and the characteristics of the fuse.

5. Improve the wiring method of the low-voltage capacitor bank of the original distribution box, and change its installation position from the top of the AC contactor to the connection between the low-voltage incoming line of the distribution box and the meter. To prevent the inaccurate measurement of the metering device when the capacitor circuit is in operation due to phase failure or damage to the capacitor.