OT: Electrical

Page 2 of 2  


somewhere on the neutral conductor for the circuit the GFI is on.
Another possibility is a mouse making contact between two conductors (don't scoff, I've seen that happen).
Something strange is going on here, which is why I advised Brian to get an electrician out ASAP. Tough to try to diagnose this from 800 miles away. Somebody needs hands-on.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
email.me:

contact with an equipment grounding conductor.
Not very likely, I'll grant. But it's still a possible scenario.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

causing stray voltage on a completely separate 120V circuit -- therefore the two circuits are not completely separate.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 7/11/2013 12:32 PM, snipped-for-privacy@garagewoodworks.com wrote:

Did you test with the stove breaker ON, but the stove itself not plugged into the outlet? I don't have a particular scenario in mind, but you might as well find out if the stove itself has anything to do with it.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thursday, July 11, 2013 12:40:49 PM UTC-4, Greg Guarino wrote:

e oven light on. Now it's started to throw the same GFI at random times ev en when the oven is not in use.

cuit) the 110V GFI checks out 'correct' with the tester.

tlet and turn the breaker 'on' for the stove circuit the two right lights o n tester go dim and the left most light flickers. When stove is unplugged and I repeat there is no difference at tester when circuit is in 'on' or 'o ff' position at breaker.

Yes. It tests normal.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@garagewoodworks.com wrote in

Please note that this does *not* prove that the problem is in the stove.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 7/11/2013 11:43 AM, snipped-for-privacy@garagewoodworks.com wrote:

Don't laugh, did you test with your TS plugged in and running? I would want to eliminate the possibility of the circuit being used being the problem.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thursday, July 11, 2013 1:08:49 PM UTC-4, Leon wrote:

the oven light on. Now it's started to throw the same GFI at random times even when the oven is not in use.

ircuit) the 110V GFI checks out 'correct' with the tester.

outlet and turn the breaker 'on' for the stove circuit the two right lights on tester go dim and the left most light flickers. When stove is unplugge d and I repeat there is no difference at tester when circuit is in 'on' or 'off' position at breaker.

I'd have to swap out the plug on the saw to fit the 50A 220V receptacle. M ight be worth the trouble.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 7/11/2013 12:13 PM, snipped-for-privacy@garagewoodworks.com wrote:

I think it will certainly tell you if it is the wiring or the oven.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Greg Guarino wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@garagewoodworks.com wrote in

Not all three-light testers are the same; it would help to know if yours is the same as mine: (Amazon.com product link shortened)
Assuming that it is, then this pattern of lights means that you have hot current on both the ground and the neutral.
If you don't have a voltmeter, get one. The Harbor Freight $2.99 multimeter is actually a pretty decent piece of gear.
Then do these tests:
1. Unplug the stove, turn the breaker for the stove circuit ON, and turn the breaker for the GFI outlet OFF. Measure voltage between hot and neutral, hot and ground, and neutral and ground at the GFI outlet. All three readings should be zero (or possibly a small fraction of 1V). Plug your tester into the outlet. All three lights should be off. If you read voltage here, or if the tester lights up, STOP, call an electrician.
2. Check voltage at the stove receptacle: hot1 to hot2 (240V expected), hot1 to neutral (120V), hot1 to ground (120V), hot2 to neutral (120V), hot2 to ground (120V), neutral to ground (zero). [If the stove has a three-wire plug, omit the hot to neutral tests.]
3. Turn the stove breaker OFF, and the outlet breaker ON. Repeat the voltage measurements at the stove receptacle. All voltages should be zero.
4. Repeat the voltage measurements at the GFI. Hot to neutral and hot to ground should be 120V, neutral to ground should be zero.
5. With the stove still unplugged, measure the resistance between the two hot prongs on the stove plug. I think you'll see something between 5 and 10 ohms.
6. Measure the resistance between each hot prong and the ground prong on the plug. If it's a 4-wire plug, repeat for hot to neutral. Let me know what you get for these measurements.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 12 Jul 2013 18:46:34 +0000 (UTC), Doug Miller

5 to 10 ohms across L1 to L2? That would be a 25 amp load with everything shut off. I don't think so!!! Between hots there should be virtually infinite resistance. Between one line and neutral/ground you should see better than 50 ohms - ideally closer to 500 ohms - which is the clock / controller load. With the oven door open that should drop to 220 ohms or less (40 watt 120 volt). Turn on any element and the line to line should drop to something less than 20 ohms.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 10 Jul 2013 23:36:35 -0700 (PDT), snipped-for-privacy@garagewoodworks.com wrote:

Just a thought, look at the stove manufactureres web site and see if they have released any service bulletins on your model.
basilisk
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thursday, July 11, 2013 2:36:35 AM UTC-4, snipped-for-privacy@garagewoodworks.com wrote:

UPDATE:
I found one loose neutral on the neutral bus bar that I tightened down. Still I was reading incorrect w/ the three light tester (TLT for here).
I found a GFI I installed a while back (dedictaed circuit) that had broken free of the dry wall. The plastic fins broke off apparently from an extension cord pull.
I replaced the two plastic fins and anchored down again. So far I am reading correct on the "faulty" gfi and the oven is plugged in w/ light on.
Lets see if she trips the gfi.
I inspected the receptacle that came loose from the drywall for signs of arching and I saw none. Looked clean.
-BG
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
One never really knows, might be a loose screw in the main circuit box. When the stove draws current it might be putting some current on the ground (safety) line. That would dump a GFI.
Martin
On 7/11/2013 1:36 AM, snipped-for-privacy@garagewoodworks.com wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@garagewoodworks.com wrote:

Does the stove/oven have a 3 Pin (L1, L2, G)or 4 Pin (L1, L2, N, G) plug?
A 3 Pin (L1, L2, G) plug indicates that any 120V loads are being fed by on leg (L1 or L2) and ground (G).
A 4 Pin (L1, L2, N, G) plug indicates that any 120V loads are being fed by on leg (L1 or L2) and neutral (N).
Either of these will generate an unbalanced load that may be significant enough to trip a GFI receptacle depending on how the circuitry in the house is wired.
The 3 Pin will be a tougher problem to chase down.
You indicate that if the stove/oven is unplugged, the GFI doesn't trip.
If that is true, the stove/oven could be the problem, especially if there is a loose connection someplace in the stove/oven or back at the panel.
Good luck.
Lew
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Only if the GFI is on one leg of the 240V circuit -- which it clearly is not, since in the original post Brian described the GFI functioning normally when the stove breaker was turned off.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 12 Jul 2013 13:31:42 -0400, "Mike Marlow"

sub-panel. I suspect they are.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 7/12/2013 3:23 PM, snipped-for-privacy@snyder.on.ca wrote:

That was my first thought ... but I usually stay out of wRec electrical threads.
--
eWoodShop: www.eWoodShop.com
Wood Shop: www.e-WoodShop.net
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yep. John T.
--- ---
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.