Can "wattage" trip a GFCI?
 

On Jan 12, 2:40*pm, David Nebenzahl wrote:
On 1/12/2011 11:27 AM DerbyDad03 spake thus:





I was discussing worklights with a friend. *I told him that I have one
of these 500 watt units:

http://www.harborfreight.com/500-wat...-shop-light-40...

In one email he said:

"I like the idea of these lights, but every time I purchase one for
use, they trip the GFCI receptacle in my garage. I've had to return
every light that I've purchased and have given up on the idea."

When I said that I've used this light in the rain more than once
without any problem, he replied with:

"I believe that it's the pure wattage requirements of these lights,
more than their quality (or lack thereof) that caused my GFCI to
trip."

Does that make any sense?

If it was an current overage the breaker would trip not the GFCI so
why would a "high wattage" device trip the GFCI?

***

First of all, let's use the right terminology. "Wattage" is meaningless;
the parameter that matters here (or not) is *current*. (Remember, P = E
x I.) GFCIs are not wattmeters.

That's exactly what I thought (knew!) and that's how I explained it to
him. That's why I told him that I have used my worklight in the rain
with no issues related to the GFCI. It was after I told him that that
he came back with the "wattage" answer.


So why does the GFCI trip? I dunno:

o Defective GFCI that gets triggered by high currents in both hot & neutral?

Well, then that sort of makes the answer to my question a "yes". A
high wattage device means higher current and a defective GFCI that
can't handle "high" (relatively) current might trip. Semantics?

o An actual ground fault with the light?

Possibly, except that he said "...every time I purchase one for use,
they trip the GFCI receptacle in my garage. I've had to return every
light that I've purchased and have given up on the idea."

I doubt that there could be a fault in every light he purchased. (I'm
not arguing...just looking at the facts of this particular situation."

Probably not a very mysterious situation, and easy enough to find the
culprit. There's usually a reason for such things; gremlins don't rule
the universe (at least not all the time).

I agree, and I'd have to lean towards a defective GFCI since he said
"So, I still bungle about with a trouble light that uses a single,
underpowered incandescent rough duty bulb."

I'll suggest that he replace the GFCI and see what happens.

Thanks!