Nema standards for motors pdf

Common North American 125 volt receptacles. Each receptacle also accepts an ungrounded plug, whether polarized or unpolarized. Different nema standards for motors pdf of contact blade widths, shapes, orientation, and dimensions create non-interchangeable connectors that are unique for each combination of voltage, electric current carrying capacity, and grounding system.

Other plug and receptacle types are for special purposes or for heavy-duty applications. NEMA WD-6 and is available from the NEMA website. Row and column table of NEMA receptacles. There are two basic classifications of NEMA connectors: straight-blade and locking.

L’ are straight blade and non-locking. Twist-locking types are used for heavy industrial and commercial equipment, where increased protection against accidental disconnection is required. A connector with ground terminal is described as having more wires than poles, e. The numeral following the hyphen is the current rating of the device in amperes.

This number is followed by the letter ‘R’ to indicate a receptacle or ‘P’ to indicate a plug. As an example, the 5-15R is the common 125 V two-pole, three-wire receptacle rated for 15 A. The L5-15R, while sharing the same electrical rating, is a locking design that is not physically compatible with the straight-blade 5-15 design. The 5-30R has the same two-pole, three-wire configuration and 125 V rating, but is rated for 30 A. Although there are several non-grounding device types in the NEMA standards, only three of them are in widespread use today. These are the two-pole 1-15, still in use in millions of buildings built before the 1960s, and the three-pole 10-30 and 10-50. X’, ‘Y’, and ‘Z’ are the “hot” line conductors.