Posts: 36,546
Threads: 3
Joined: Nov 2004
Location: RTP, NC
(11-12-2020, 03:17 PM)SLandrum Wrote: The temporary feed is a 110VAC connection, which is one hot and one neutral and hopefully one ground. Is the panel in the moved house the usual 220? Normally two hot busses and a neutral? Maybe the temporary connection has the neutral connected to what is usually the other hot bus. So jumpering to an adjacent breaker shorted the hot and neutral?
No. He has a 3' length of of cord with a male plug. Hot leg is connected to a breaker, neutral and ground on the extension cord are connected to the neutral/ground bus on the panel at the moved house - it has the neutral and ground for all of the circuits on the same bus. For the moment I'm assuming one or more of the circuits on the moved house has a ground fault.
Posts: 1,644
Threads: 0
Joined: Apr 2006
(11-12-2020, 08:01 PM)crokett™ Wrote: No. He has a 3' length of of cord with a male plug. Hot leg is connected to a breaker, neutral and ground on the extension cord are connected to the neutral/ground bus on the panel at the moved house - it has the neutral and ground for all of the circuits on the same bus. For the moment I'm assuming one or more of the circuits on the moved house has a ground fault. The moved house panel is being fed from a separate main panel so it is acting as a sub panel. The neutral in the moved house panel cannot be bonded to the ground. Refer to attached.
https://www.garagejournal.com/forum/show...p?t=345777
Look at diagram in Post 11.
It’s possible you are getting stray current running back on the ground wire from the neutral.
Posts: 64,680
Threads: 3
Joined: Feb 2007
Location: Merryland
(11-14-2020, 11:46 PM)Chuck in NC Wrote: The moved house panel is being fed from a separate main panel so it is acting as a sub panel. The neutral in the moved house panel cannot be bonded to the ground. Refer to attached.
https://www.garagejournal.com/forum/show...p?t=345777
Look at diagram in Post 11.
It’s possible you are getting stray current running back on the ground wire from the neutral.
+1
Neutral and ground must be separated at the sub panel in the moved house is now a sub panel. Neutral carries current. Without separating them, there is a ground fault. An electrician did not wire the sub panel
Posts: 1,998
Threads: 1
Joined: Aug 2016
(11-15-2020, 07:30 AM)Snipe Hunter Wrote: +1
Neutral and ground must be separated at the sub panel in the moved house is now a sub panel. Neutral carries current. Without separating them, there is a ground fault. An electrician did not wire the sub panel
Since the moved home is just sitting there and not connected to a ground there should not be a path for any neutral current which also would have been when he was connected to the first bus and ground which worked ok. I would look for a fault or a actual ground on a circuit on the second bus he connected to. Do as someone said, turn all the breakers off and see which breaker trips it. Roly
Posts: 5,653
Threads: 0
Joined: May 2005
Location: Centre County Pennsylvania
would be interesting if the gfci tripped without any breakers on.
I feel like we are due an update
Posts: 1,644
Threads: 0
Joined: Apr 2006
(11-15-2020, 09:35 AM)Roly Wrote: Since the moved home is just sitting there and not connected to a ground there should not be a path for any neutral current which also would have been when he was connected to the first bus and ground which worked ok. I would look for a fault or a actual ground on a circuit on the second bus he connected to. Do as someone said, turn all the breakers off and see which breaker trips it. Roly
Look at the circuit I referenced in previous. The neutral of the moved home is connected to the ground from the temporary supply panel. This results in a parallel circuit for return to the panel supplying the power.
It will not hurt anything to remove the “moved home” neutral-to-ground connection in the moved home panel and see if the “fault” clears.
Note: Do NOT remove the neutral-to-ground connection in the power source panel. That connection provides ground fault protection.
Posts: 1,998
Threads: 1
Joined: Aug 2016
(11-15-2020, 09:46 PM)Chuck in NC Wrote: Look at the circuit I referenced in previous. The neutral of the moved home is connected to the ground from the temporary supply panel. This results in a parallel circuit for return to the panel supplying the power.
It will not hurt anything to remove the “moved home” neutral-to-ground connection in the moved home panel and see if the “fault” clears.
Note: Do NOT remove the neutral-to-ground connection in the power source panel. That connection provides ground fault protection.
Since the ground is not connected to anything at the moved house there is no parallel path. Also the connections he made to the first bus and neutral everything worked, something is faulted or grounded on the second bus connection, if it had a return path on the ground it would have tripped then also. Roly
Posts: 36,546
Threads: 3
Joined: Nov 2004
Location: RTP, NC
11-16-2020, 12:55 PM
(This post was last modified: 11-16-2020, 12:57 PM by crokett™.)
(11-15-2020, 09:38 PM)EricU Wrote: would be interesting if the gfci tripped without any breakers on.
I feel like we are due an update
No it doesn't. The extension cord is wired to 2 breakers, one for each side of the breaker bus. Either of those can be on and some of the other breakers can be on and the GFCI doesn't trip. however, the new problem is the breakers that do trip the GFCI keep changing. I identified 1, on one side of the bus. an hour later, that 1 and another on the other side of the bus that worked previously were causing a problem. since I know that a subpanel should not have ground and neutral bonded and the moved house panel has them bonded, we're going to start with a temporary bus bar and move all the neutrals to it.
Posts: 1,998
Threads: 1
Joined: Aug 2016
(11-16-2020, 12:55 PM)crokett™ Wrote: No it doesn't. The extension cord is wired to 2 breakers, one for each side of the breaker bus. Either of those can be on and some of the other breakers can be on and the GFCI doesn't trip. however, the new problem is the breakers that do trip the GFCI keep changing. I identified 1, on one side of the bus. an hour later, that 1 and another on the other side of the bus that worked previously were causing a problem. since I know that a subpanel should not have ground and neutral bonded and the moved house panel has them bonded, we're going to start with a temporary bus bar and move all the neutrals to it.
Going back to my original response of too much capacitance in the circuit due to excessive circuit length, normally over 150'. If you dont have the ground bus grounded anywhere it should not trip because of a parallel path. Try plugging the extension cord in a non gfci outlet and place a gfci in or near the moved house and see if it trips. Roly
Posts: 36,546
Threads: 3
Joined: Nov 2004
Location: RTP, NC
(11-16-2020, 02:49 PM)Roly Wrote: Going back to my original response of too much capacitance in the circuit due to excessive circuit length, normally over 150'. If you dont have the ground bus grounded anywhere it should not trip because of a parallel path. Try plugging the extension cord in a non gfci outlet and place a gfci in or near the moved house and see if it trips. Roly
Interesting suggestion on too much capacitance. I suggested a GFI outlet at the moved house, because at least we don't have to walk the 150' to reset the breaker. I'll suggest that to him.
|
