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jmthomas56
Jun 18, 2010, 10:29 PM
Hi,
I cut the extension cord while trimming the hedges, now 2 gfi's won't reset, one outside on front of house, the other outside on back of house. I replaced both gfi's and still have the same problem.
What else can I check? None of the breakers in the panel were tripped. I did turn each one off then back on. Still have no power to gfi's
Thanks,
J
tkrussell
Jun 19, 2010, 03:32 AM
Assuming the breaker is not defective, the short circuit caused a loose connection to open clear. Need to check each wire connection and splice from the panel to the receptacles.
stanfortyman
Jun 19, 2010, 04:17 AM
You may have another GFI upstream of the two not working. Someone may have wired them using line and load, so when it tripped it killed the two downstream.
hkstroud
Jun 19, 2010, 04:31 AM
now 2 gfi's won't reset
Cutting the cord should have only tripped the one being used.
Therefore, I'd bet on Stan.
tkrussell
Jun 19, 2010, 04:45 AM
Since when did answering questions here turn into a competition?
Therefore, I'd bet on Stan.
Are you saying my advice is not valid and Therefore, not possible?
creahands
Jun 19, 2010, 05:17 AM
Am I allowed to bet too? How much can I bet if allowed? Where do we go to collect if a winner?
Chuck
hkstroud
Jun 19, 2010, 05:29 AM
No, of course not TK. Just an expression, if it were a competition, I'd lose. Just noting that two GFI's tripped. Haven't had your second cup of coffee yet have you?
Chuck, The opening bet is a pizza.
Stratmando
Jun 19, 2010, 06:51 AM
I would guess their is another GFI, or a breaker tripped and not thrown, Modern GFI's won't reset if no power is present on Line side.
Line and load reversed after reinstalling?
tkrussell
Jun 19, 2010, 07:10 AM
I have plenty of coffee, thanks, perhaps too much, but not going to stop.
Poster never stated that the GFI's were tripped, cord got cut and power stopped, he tried to rest GFI's thinking that was the problem, then tried resetting the breaker.
GFI receptacles will not trip or reset when power is not on to the devices.
The act of cutting the cord created a short circuit, not a ground fault. While cutting the cord if the hot and equipment ground came in contact first, that would be a ground fault, but the hot came in contact with both the neutral and the equipment ground, nearly at the same moment.
A short circuit causes the current to flow quickly and very high. Depending on the available interrupting current from the utility, the short circuit current can approach 10,000 amps in a very short amount of time, milliseconds, or even quicker. Often this event is measured in cycles, rather that seconds.
A loose connection, such as a poorly made splice, a cut in the wire, a loose screw, will not be able to handle this amount of current. Arcing occurs at this location. The arcing melts the metal at the poor connection, that even though was connected and allowing normal current to pass, is now compromised by the melted metal, and the connection is now opened.
Wire connections that are pushed into the back of receptacles, called among other things, QuikWire, Whiz Wire, Stab in the Back, etc. are popular for these kinds of problems.
Not too often are GFI receptacles protected by other GFI receptacles, but poor connections are very popular. I have traced and repaired many poor connections that had opened due to a short circuit that did not trip the breaker, seldom have I found a GFI protecting a GFI.
Statistically speaking, you took on a losing bet.
donf
Jun 19, 2010, 12:03 PM
Way to go TK!
Stratmando
Jun 20, 2010, 04:37 AM
Back wired recepticles are a major problem as TK mentions.
I would plug in an extension cord into a known good outlet and bring the end of the cord next to a bad receptacle,
Then one test lead in the cords hot and the other in the recepticles neutral, and then check for power between the cords neutral(large slot) and the recepticles hot, If bot hot and neutral are lost it is GFI related, If 1 conductor lost integrity(hot or neutral) it is a wiring or breaker problem. Actually you will have to remove the GFI's to Test the conductors.
I did this test 1 time with an extension cord and found the Hot , Neutral AND Ground were lost, It turned out to be a Roofer cut through the romex.