Low voltage switchgear installation requirements

1 When selecting a low-voltage power distribution device, in addition to the nominal voltage, frequency and calculated current of the circuit in which it is located, the dynamic and thermal stability under short-circuit conditions should also be met. The short-circuit current protector should be capable of having an on-off capability under short-circuit conditions.

2 The layout of the power distribution device should consider the convenience of operation, handling, maintenance and testing of the equipment. There shall be no exposed lighting or power line crossings above the exposed and live parts of the distribution equipment (except for power distribution units with a protective enclosure at the top).

3 distribution screens arranged in rows, when the length exceeds 6m, the passage behind the screen should have two outlets leading to the room or other rooms, distributed at both ends of the passage. When the distance between the two outlets exceeds 15 m, the outlet is also increased. The width of the channel behind the screen before the screen cannot be less than the value given in the table below.

Channel width before and after the low-voltage power distribution panel Unit: m

4 The exposed electrified body above the low-voltage distribution room channel should not be lower than the following values:

a. The width of the front channel of the screen is 2.5m. After the net is added, the height can be reduced, but the minimum height of the net is 2.2m.

b. The width of the channel behind the screen is 2.3m. Otherwise, the cover should be covered. The height after the cover should not be lower than 1.9m.