Protection circuit to prevent the external circuit failure of distribution box power supply

For the distribution box with distribution transformer capacity of 100kV · A and above, the temperature control relay (ju-3 or ju-4 ultra small temperature relay) and axial flow fan shall be installed on the box on the left side above the control electrical panel, so that when the temperature in the box reaches a certain value (such as 40 ℃), the exhaust fan can be automatically started and the heat can be forced out Heat the box.

The protection circuit is adopted to prevent the occurrence of the external circuit fault supplied by the distribution box. For example, da88cm-ii motor phase loss protection module can be installed in the distribution box to prevent the motor from burning due to low-voltage phase loss operation.

Improve the wiring mode of the low-voltage capacitor bank of the original distribution box, and change its installation position from the pile head on the AC contactor to the connection between the low-voltage incoming line of the distribution box and the meter.

In order to prevent the inaccurate measurement of the metering device caused by the phase failure of the capacitor circuit or the damage of the capacitor in operation. In addition, the capacitor selection model shall be bsmj series products to ensure reliable and safe operation of components.