Plug type A and B (NEMA plug) Plug types A and B, also known as NEMA plugs, are mainly used in the USA, Canada, Mexico and Japan. The NEMA plug is named after the National Electrical Manufacturers Association. Plug types A and B are used for power distribution units in server racks in IT environments as well as in AV installations. This plug is also available in the variants NEMA-1 to NEMA-6. Structure of the NEMA plug The NEMA plug has two flat parallel contacts that are electrically conductive. This applies to both plug type A and plug type B. The difference for plug type B is an additional round pin that serves as a protective contact conductor. This conductor ensures a higher level of safe earthing to prevent electric shocks. NEMA-5 or plug type B is the most common in the USA, which has a mains voltage of 120 V at 60 Hz and a single-phase alternating voltage. GUDE’s power distribution units are available with load outputs for plug type B, among others, and are manufactured as standard. The plug type B in power distribution units provides a safe and reliable power supply in server racks. World map with connector types