2 amps, too much?

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ptonsparky

ptonsparky

Tom
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
Local machine shop purchased an Ultrasonice Parts cleaner that would trip the GFCIs. We checked the current on the EG and sure enough just plugging it in would would exceed 5 ma. Seriesed Fluke Digital VOM.

Operating, with the Heater and Ultrasound, would exceed 2 amps on the EG. How much is to much? We gave it a seperate single receptacle.

Seems awful high for a new piece of equipment.
 
don_resqcapt19

don_resqcapt19

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Location
Illinois
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retired electrician
I don't know what the limit is for industrial equipment, but for appliances the UL standard sets the maximum leakage current at 0.5 mA or 1/10 the GFCI trip point.
 
don_resqcapt19

don_resqcapt19

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Location
Illinois
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retired electrician
cowboyjwc said:
Before you start sending equipment back, make sure, as was already mentioned, that a GFCI receptacle is even necessary.
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Even if a GFCI protection is not required, 2 amps of current on the EGC indicates a serious safety hazard to me.
 
cowboyjwc

cowboyjwc

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Location
Simi Valley, CA
Thing is, if the building is right, if he as two amps on the ground, he has two amps on all the grounds. Make sure it's that piece of equipment

Also if he's sending two amps through the grounds why aren't any of the other GFCI's, if there are any, tripping?

And is it really going through the EG or grounded conductor?
 
ptonsparky

ptonsparky

Tom
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
No, the area is not required to have GFCI, but we normally install them.

i think the equipment is defective and expressed the concern to the owners. They talked to the mfg who said absolutely not to the GFCI. I did not get to talk to them.

We settled on the single device with the warning to them that the EG must be maintained.
 
kwired

kwired

Electron manager
Location
NE Nebraska
cowboyjwc said:
Thing is, if the building is right, if he as two amps on the ground, he has two amps on all the grounds. Make sure it's that piece of equipment

Also if he's sending two amps through the grounds why aren't any of the other GFCI's, if there are any, tripping?

And is it really going through the EG or grounded conductor?
Click to expand...
Why should other GFCI's trip? They don't monitor the EGC.
 
Z

zbang

Senior Member
Location
Roughly 5346 miles from Earls Court
oldsparky52 said:
If someone gets hurt, and it's traced back to this, I don't see how that warning will get you out of the liable path.
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2 amps on the EGC? How many buildings even leak that much? If the measurement is correct, you'll never convince me that it isn't defective.

To rewrite two of the questions-
Does the mfg require GFCI, require NO GFCI, or even have an opinion at all?
Does the location require GFCI.
 
don_resqcapt19

don_resqcapt19

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Location
Illinois
Occupation
retired electrician
cowboyjwc said:
Somewhere the EG is bonded to the grounded conductor.
Click to expand...
Maybe, but there could be other defects in the equipment that would cause current to flow on the EGC.
It was tripping his, wasn't it?
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As I understand it, it was tripping the GFCI that was supplying power to the (defective) equipment.

I would strongly advise the customer not to use this equipment. If the equipment is listed, I would contact the listing agency.
 
cowboyjwc

cowboyjwc

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Staff member
Location
Simi Valley, CA
don_resqcapt19 said:
Maybe, but there could be other defects in the equipment that would cause current to flow on the EGC.

As I understand it, it was tripping the GFCI that was supplying power to the (defective) equipment.

I would strongly advise the customer not to use this equipment. If the equipment is listed, I would contact the listing agency.
Click to expand...

Only reason I bring things up is, because we are only getting his version of reality.

Had a guy try to tell me the other day that I was an idiot because I required a second ground rod, but he didn't need it because he measured it and he had less than 25 ohms to ground. I said let me guess you used your ohm meter to check it. Yes. Yeah add a second ground rod and then do some research on how you measure ohms at the ground rod.
 
ptonsparky

ptonsparky

Tom
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
EC - retired
The parts cleaner was sitting on an isolated roll about table. I made a cord so I could insert the meter into the EG to measure the current. I expected enough to trip a GFCI, not much more. Current was not flowing from the building wiring thru the cord EG then to the case and to earth via metal frame of table.

GFCIs are not required by location. MFG says no way will it work on a GFCI. That is an understatement.
 
K

keith gigabyte

Senior Member
Location
New Kensington, Pa
cowboyjwc said:
Thing is, if the building is right, if he as two amps on the ground, he has two amps on all the grounds. Make sure it's that piece of equipment

Also if he's sending two amps through the grounds why aren't any of the other GFCI's, if there are any, tripping?

And is it really going through the EG or grounded conductor?
Click to expand...


what you brought up is why I asked to check ground lights. The gfci possibly won't trip depending on setting. A gfci on a breaker is different than personnel gfci.
personel gfci are 4 to 6 ma. And wiring/breaker gfcis I've seen set as high as 7 amps.
 
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