How to choose lighting Pole Top Box and switch box appliances?

The selection of lighting Pole Top Box, switch box and switching appliances can ensure the reliable disconnection of power supply under normal and fault conditions. In case of leakage, the leakage equipment can be quickly disconnected from the power supply. There are obvious power-off switches during maintenance. We should pay attention to the following principles when selecting lighting Pole Top Box and switch box appliances.

1. The switching appliances used in the lighting Pole Top Box shall be qualified products. Whether choosing new appliances or continuing to use old appliances, they should be intact, reliable operation and good insulation.

2. The switchgear that can cut off and isolate the power supply in any case shall be set in the cabinet. Manual disconnectors are usually used as switching circuits under no-load conditions. Automatic switch, contactor, etc. It is used to turn on and off the circuit under normal load and fault.

3. The switchgear of the lighting Pole Top Box shall correspond to the distribution line one by one, and the shunt shall be set to ensure the control of the special road. The rated value and action setting value of the main switchgear and shunt switchgear shall be appropriate to ensure that they can act step by step in case of fault.

4. The "one machine, one switch" system shall be implemented between the lighting Pole Top Box and the electrical equipment to prevent misoperation caused by "one machine, multiple switches". The rating of the switchgear in the switchgear box shall be compatible with the rated capacity of the electrical equipment.

5. The leakage protector shall be set in the box, and its rated leakage action current and leakage action time shall be reliable. Generally, the rated leakage action current is less than or equal to 30mA, the rated leakage action time is less than 0.1s, and reasonable grading coordination is provided.

6. Manual switching devices are only allowed to be used for small capacity electrical equipment (less than 5.5kW) and lighting circuits. The high-capacity power supply circuit, especially the motor circuit, is slow to switch on and off manually, which is easy to cause strong electric arc to burn people or electrical appliances. It shall be controlled by automatic switch or contactor.

The above are the principles for selecting lighting Pole Top Box and switch box electrical appliances. When installing Pole Top Box, we should choose the installation location to avoid damp, direct sunlight and corrosive places to prevent rapid insulation aging.