Is it permissible to stub up conduits into the bottom of a stationary generator enclosure and continue the conductors out of the conduit directly into the generator itself, or…

Question

Is it permissible to stub up conduits into the bottom of a stationary generator enclosure and continue the conductors out of the conduit directly into the generator itself, or do I need to continue the conduit to the generator termination box?

Answer

It is permissible to stub up conduits into a generator enclosure and have exposed conductors inside of the generator enclosure provided that the generator is mounted on a non-combustible surface such as concrete. Stationary generators are evaluated for compliance with the Standard for Safety for Stationary Engine Generator Assemblies UL 2200 and Listed under the product category Stationary Engine Generators (FTSR), located on page 150 in the 2010 UL White Book. You can also access the Guide Information for FTSR on UL’s Online Certification Directory at www.ul.com/database and enter FTSR at the Category code search field.

UL 2200 requires that engine generators be provided with a complete enclosure. The bottom of the enclosure can be mounted on a non-combustible surface such as concrete, similar to an open bottom switchboard. Conduit stubs ups into the enclosure may expose conductors within the enclosure; however, connection to the generator terminations box must be in compliance with the installation instructions and the NEC and be accessible to the AHJ for inspection.

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