Low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. Electrical safety. Equipment for testing, measuring or monitoring of protective measures. Part 7. Phase sequence
Rectangular iron all-cast moulding boxes with simplified wall profile having inside dimensions: length from 400 to 500 mm, width from 300 to 400 mm, height from 75 to 200 mm. Construction and dimensions