• The Joint International Committee (JIC) developed a standard set of symbols for representing electrical circuit elements. These are given below:
• NEMA has provided a set of ratings for cabinets housing voltages less than 1000V AC. The basic classifications are outlined below,
Type 1 - General purpose - indoors
Type 2 - Dirt and water resistant - indoors
Type 3 - Dust-tight, rain-tight and sleet(ice) resistant - outdoors
Type 3R- Rainproof and sleet(ice) resistant - outdoors
Type 3S- Rainproof and sleet(ice) resistant - outdoors
Type 4 - Water-tight and dust-tight - indoors and outdoors
Type 4X - Water-tight and dust-tight - indoors and outdoors
Type 5 - Dust-tight and dirt resistant - indoors
Type 6 - Waterproof - indoors and outdoors
Type 6P - Waterproof submersible - indoors and outdoors
Type 7 - Hazardous locations - class I
Type 8 - Hazardous locations - class I
Type 9 - Hazardous locations - class II
Type 10 - Hazardous locations - class II
Type 11 - Gas-tight, water-tight, oiltight - indoors
Type 12 - Dust-tight and drip-tight - indoors
Type 13 - Oil-tight and dust-tight - indoors
