NEC Article 590 stipulates the electrical safety measures for temporary power. Learn more about the ground fault protection required at your construction site.

NEC Article 590 and all of its subsets are in relation to Temporary Installations. This means that it involves the electrical protection provisions for all temporary electrical power and lighting installations. Subset 590.6 (and more specifically 590.6(A)), dives into the mandated GFCI for temporary powered products. This subset, and all of its extensions, include:

This section is the specific destination for Ground-Fault Protection for the personnel working with all temporary wiring installations in a plethora of different working environments (from demolition, construction, remodeling, repair, and maintenance, etc.). The Article also states that it needs to comply with requirements set in 590.6(A) & (B).

This section states (specifically for receptacle outlets) for the temporary use power to equipment in the stated locations (from section 590.6) need to comply with the requirements of 590.6(A)(1) through 590.6(A)(3). These sections state, in order:

1.) This part is for the receptacle outlets that are not part of the permanent venue wiring. This including 125VAC, single-phase, up to 30-Amp configured receptacles that are not a part of the fixed wiring of the building /structure, and which are in use by personnel must encompass ground-fault circuit-interrupter (GFCI) protection. On top of this, any required GFCI protection for personnel, listed cord sets/devices incorporating Listed GFCI protection must be of the portable construction type. 2.) This section is for the existing receptacles that are a part of the permanent infrastructure. They will require GFCI protection for personnel for all 125VAC, single-phase, up to 30-Amp receptacle outlets. Just as the previous section, this is accomplished with the use of “portable type” listed cord sets/devices. 3.) The last extension of subset 590.6(A) is concerning receptacles integral to a 15kW or smaller portable generator. Panel integrated 125VAC and 125/250VAC, single-phase, up to 30-Amp receptacle outlets shall provide listed ground-fault circuit-interrupter (GFCI) protection for personnel. This section also goes on to dictate that “if used in a wet/damp location, follow the guidelines from Article 406(A) & (B) (which dictates that they be weather resistant listed, and incorporate hinged doors for increased ingress protection).

This section gives fairly the same information, except it is the rules & regulations for “other” (as in other than the mentioned locations from 590.6(A)) receptacle outlets.

All and all, NEC 590 dictates the standards for electrical protection of temporary power supply operations, which also tie in similarly with OSHA standards in this instance. The section also makes sure to list when and where you need ground fault protection on a job site, which in most cases is everything under 125VAC and 30 Amps needs to have Class A (6mA) GFCI protection.

1. 15 Amp Inline GFCI
2. 15 Amp Plug GFCI
3. 20 Amp Portable GFCI
4. 30 Amp Permanent GFCI
5. 30 Amp Portable GFCI
6. 60 Amp 3-phase GFCI
7. 60 Amp SPGFCI