For distribution boxes that handle only lighting circuits or small power loads, if the incoming wire size is less than 10 square millimeters and the number of circuit switches is fewer than 20, the width of the box should be calculated by summing the width of the switches. For distribution boxes that handle only lighting circuits or small power loads, if the incoming wire size is less than 10 square millimeters and the number of circuit switches is fewer than 20, the width of the box should be calculated by summing the width of the switches. The enclosure protects the electrical components from water, dust, and damage. When choosing one, check the IP or NEMA rating. A higher rating means better protection — especially useful for outdoor or industrial use. Single Phase Distribution Box generally consists of Double Pole MCBs, Single Pole MCBs, and RCCBs. three phase lines a, B and C (generally yellow, green and red), one zero line (light blue) and one ground line (yellow with green stripes).
[PDF Version]