Enclosures (other than fences or walls) around electrical equipment such as switchboards, panelboards, industrial control panels, motor control centers, meter sockets, switches, transfer switches, power outlets, circuit breakers, adjustable-speed drive systems, pullout switches, portable power distribution equipment, termination boxes, general-purpose transformers, fire pump controllers, fire pump motors, and motor controllers, with a voltage rating not exceeding 600 volts and that are meant to be used in certain locations, should be marked with a specific enclosure-type number as listed in Table 110.28.
Enclosures of electrical equipment such as switchboards, panelboards, industrial control panels, motor control centers, meter sockets, switches, transfer switches, power outlets, circuit breakers, adjustable-speed drive systems, pullout switches, portable power distribution equipment, termination boxes, general-purpose transformers, fire pump controllers, fire pump motors, and motor controllers, with a voltage rating not exceeding 600 volts, meant for use in certain locations, should be marked with a specific enclosure-type number as listed in Table 110.28. Enclosures that meet the requirements for multiple types of enclosures can be marked with multiple designations. Additionally, enclosures marked with a type can also be marked with the following:
A Type 1 may be marked “Indoor Use Only.”
A Type 3, 3S, 4, 4X, 6, or 6P may be marked “Raintight.” A Type 3R may be marked “Rainproof.”
A Type 4, 4X, 6, or 6P may be marked “Watertight.”
A Type 4X or 6P may be marked “Corrosion Resistant.”
A Type 2, 5, 12, 12K, or 13 may be marked “Driptight.”
A Type 3, 3S, 5, 12K, or 13 may be marked “Dusttight.”
Enclosures of electrical equipment such as switchboards, panelboards, industrial control panels, motor control centers, meter sockets, switches, transfer switches, power outlets, circuit breakers, adjustable-speed drive systems, pullout switches, portable power distribution equipment, termination boxes, general-purpose transformers, fire pump controllers, fire pump motors, and motor controllers, with a voltage rating not exceeding 600 volts, meant for use in certain locations, should be marked with a specific enclosure-type number as listed in Table 110.28. Enclosures that meet the requirements for multiple types of enclosures can be marked with multiple designations. Additionally, enclosures marked with a type can also be marked with certain descriptions such as “Raintight”, “Rainproof”, “Watertight”, “Corrosion Resistant”, “Driptight”, and “Dusttight”. An example of this is a label for a transformer with a circled area on the label indicating an enclosure type of 3R.
Table 110.28 should be used to select appropriate enclosures for electrical equipment such as switchboards, panelboards, industrial control panels, motor control centers, meter sockets, switches, transfer switches, power outlets, circuit breakers, adjustable-speed drive systems, pullout switches, portable power distribution equipment, termination boxes, general-purpose transformers, fire pump controllers, fire pump motors, and motor controllers, with a voltage rating not exceeding 600 volts, meant for use in non-hazardous (unclassified) locations. The enclosures are not intended to protect against condensation, icing, corrosion, or contamination that may occur inside the enclosure or enter through conduit or unsealed openings.
A new informational note was added to Table 110.28 that references IEC ingress protection
NEC Electrical Code
ratings, which may be indicated on some enclosures. These ratings are not a substitute for the
type ratings in the table.
