bonding @ reducing washers

[rcampbell]

I've been getting many mixed answers as to whether or not code requires bonding bushings or locknuts around reducing washers above 250V. I,m doing a job w/ the dumbest can lights I've ever seen...there are (2) 3/4" KO's and (1) 1/2" KO. Piping it in 3/4" is out of the question as I've already done it in 1/2", planning to go in and out of the lights, while I waited for the fixtures to arrive (they're above a drywall ceiling). While the code seems to say I need to ("when encountering an oversized knockout") I'm also hearing that the UL white book lists donuts as suitable for the purpose. Any definitve thoughts? (There is an equip. ground in the raceway).

Thanks,

A young , confused foreman

 

[allenwayne]

This discussion has been on the burner before.The reducing washers are listed as being a suitable connection so no migb is needed.But on a concentrical KO it is go figure

 

[George Stolz]

I'm doing a job w/ the dumbest can lights I've ever seen...

You too? I've been cursing cans the last couple of days too!

While the code seems to say I need to ("when encountering an oversized knockout")....

I'd say that a reducing washer would fall under 250.92(B)(4), or if that isn't considered persuasive enough, then 250.94's exception, list item #4 would cover them too.

I'm also hearing that the UL white book lists donuts as suitable for the purpose. Any definitve thoughts?

Here is a quote from the white book:

Metal reducing washers are considered suitable for grounding for use in circuits over and under 250 V and where installed in accordance with ANSI/NFPA 70, "National Electrical Code."

You can see it for yourself, click here.

I'm not saying I think it's a great idea, but I am saying I believe it to be perfectly legal. In this particular circumstance, with a conductor pulled for an EGC, then the conduits themselves are at the most risk.

I would pay close attention when pulling in the conductors, and be certain no abrasion is happening, and then trust the reducing washers with a jaundiced eye, IMO. Hope that helps.

 

[monkey]

rcampbell, sounds like a real pain. Will the area above the ceiling be acessable? If so, you could pipe to some j boxes, then whip out from each j box with a number of whips, one to each can.