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I know EMT can be used as its own grounding path, and no separate grounding ("green" or bare) conductor is required within the conduit, but what fitting do I need at the panel to complete the grounding path? Is a grounded bushing required for voltages under 250V (I'm running a 120V, single-phase circuit in this case)?

Please let me know if I've left out any critical info for my install. This is a simple branch circuit with a couple of 20A outlets in my garage. Code citations are always appreciated.

Thanks!

2 Answers 2

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The standard metal coupling suffice, if you install them properly.

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This one is a compression style coupling, but the setscrew style will suffice as well.

You make the ground contact by running that conduit nut down and bapping it tight with a screwdriver blade and hammer... and tightening the compression fitting or setscrew. After 50 years in a quasi-outdoor building, I can attest that it works fine.

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You just need an EMT connector and locknut (and to make sure that there's no paint in the way)

You don't need the extra work of a grounding bushing for voltages under 250V, even when concentric or eccentric KOs are present, provided you're not dealing with service entrance wiring. This is implied by the lack of a specific bonding requirement for such circumstances in NEC 250.97, and is spelled out in section 4.7.6 of NECA-NEIS 101, the Standard for Installing Steel Conduits (RMC, IMC, EMT) (parts not relevant to conduit-to-box bonding omitted):

Metal raceways for feeder and branch circuits operating at less than 250 volts to ground shall be bonded to the box or cabinet. Do one or more of the following:

• Use listed fittings.

• For steel RMC or IMC, use two locknuts one inside and one outside of boxes and cabinets.

• Use fittings, such as EMT connectors, with shoulders that seat firmly against the box or cabinet, with one locknut on the inside of boxes and cabinets.

NOTE: Remove paint in locknut areas to assure a continuous ground path. Repaint or cover any exposed area after installation is completed.

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