15 amp receptacles on 277V/30 amp lighting circuit for LED ballasts

[OneTallShort]

Use Case:
Commercial location (Greenhouse Growth lighting)
277V 30 amp lighting branch circuit
~660 watt LED ballasts
Looking at specifying l7-15p cord and plug connected (twistlock) 15 amp receptacles
For example a duplex Leviton 4750

4750

www.leviton.com

So are these 15 amp receptacles legal for LED ballasts in recent code versions?

410.62 (C) 2 and 3 both allow "Inlets and connectors shall be permitted to be of a lower ampere rating than the branch circuit but not less than 125 of the luminaire load current." C.2 specifically allows branch circuits to 50 amps. Interesting that C.3 doesn't mention the branch circuit size...

660 watts/ 277V*1.25 = ~3 amps so that works for a 15 amp receptacle.

The problem is that neither 2 (Provided with Mogul-base, Screw Shell Lampholders) or 3 (Equipped with Flanged Surface Inlet) seem to apply to a remote LED ballast that is cord connected to a light engine.

I'm not sure what "Equipped with Flanged Surface Inlet" is referring to for a lighting fixture. Examples?

An example of the high wattage cord connected LED lighting fixtures in the use case:

VYPR Series

Built for year-round production, the Fluence VYPR Series empowers the growers to have predictable production despite the season.

fluence.science

My take is that #2 covers a 1000w HPS HID (remote) ballast, which is a very similar application. But maybe the code hasn't caught up to LED's yet?

Now if the 277V lighting branch circuit drops to 20 amps, I'm pretty sure there aren't any code issues with those receptacles, as 15 or 20 amp receptacles can be used on any (most?) 20 amp circuit.

Thanks,

Gregg Short P.E.
Greenhouse Design LLC
Burbank, OH

 

[mbrooke]

I know this was done with twist lock receptacles feeding high bay HID lights. The circuit was often 30 amps on a 15 amp outlet.

 

[Fred B]

......

I'm not sure what "Equipped with Flanged Surface Inlet" is referring to for a lighting fixture. Examples?
.......

Your fixture would have something of this nature as part of it, or any number of similar configurations.

 

[Meltric_South]

I really struggle to understand why any receptacle or plug is permitted to be used in a branch circuit with a lower amp rating than the OCPD. There is no guarantee that someone won't hook up a larger load to a receptacle, and if the circuit will supply the amps it basically turns the P/R into the OCPD.

 

[tortuga]

I am not sure why that exception is still there,
when HID ballasts had those heavy transformers that provided current limiting and that made sense.

I'd check with the manufacturer that they are listed for circuits over 20A.

For an electronic retro fit and LED replacement ballasts on circuits over 20Amp I would want to see those little supplemental fuses on the fixture.
With all the lighting having to be on a GFCI in the 2020NEC its probably not that big of an issue.