subpanel
#1
subpanel
about 10 years ago i installed a subpanel in a detached garage i built, in oregon. at that time i was told by 2 different electricians, that i eather had to ground the panel with a grounding rod, or i could run a ground from the main panel and would not have to install a grounding rod. I have been reading conflicting info here , some have said you need both, i ran 2 # 6 wires, a # 8 for the ground, the ground was used to ground the subpanel, all the nuetrals inside the panel were isolated from the ground, why would a grounding rod be needed?
#2
For a detached structure with a sub-panel, a ground rod was/is always required.
The question is whether or not you need to run a ground wire from the house.
If you run a ground from the house then the grounds and neutrals in the sub are kept separate. If you do not run a ground wire then the grounds and neutrals are put to the same bars.
It is generally recommended to run a ground wire. This has been gone over a thousand times so if you do a search of this forum you will get a ton of good information as to why.
A neutral is always required. Did you run one, or just the two hots and ground?
The question is whether or not you need to run a ground wire from the house.
If you run a ground from the house then the grounds and neutrals in the sub are kept separate. If you do not run a ground wire then the grounds and neutrals are put to the same bars.
It is generally recommended to run a ground wire. This has been gone over a thousand times so if you do a search of this forum you will get a ton of good information as to why.
A neutral is always required. Did you run one, or just the two hots and ground?
#3
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Are you saying that you installed a 120 volt sub panel? Whay only a 120 volt sub panel?
Yes, you need a ground rod. The ground rod is for safety. The ground rod and the ground wire serve different purposes.
Yes, you need a ground rod. The ground rod is for safety. The ground rod and the ground wire serve different purposes.
#4
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You are always required to have ground rods at a structure when you run a subpanel. The ground rods are required so that the system will be at _local_ ground potential.
You may have been confused by the fact that there are _two_ different ways of connecting the actual electrical supply to ground in a detached structure. You can _either_ run a separate equipment ground conductor with the supply conductors, and then isolate the ground and neutral in the sub-panel (in other words, you do a normal sub-panel install) _or_ you can just run a neutral, and then bond the neutral to your grounding system in the detached structure. In other words, you could do an install that looks like a main service, even though it is a subpanel; you may only do this in a detached structure with no bonded metallic paths between the structures.
In either case you must have the ground rods.
I was confused by something: was this a 120V or a 240V subpanel? You describe three wires (2 #6 and 1#8); which is hot, which is ground, and which is neutral?
-Jon
You may have been confused by the fact that there are _two_ different ways of connecting the actual electrical supply to ground in a detached structure. You can _either_ run a separate equipment ground conductor with the supply conductors, and then isolate the ground and neutral in the sub-panel (in other words, you do a normal sub-panel install) _or_ you can just run a neutral, and then bond the neutral to your grounding system in the detached structure. In other words, you could do an install that looks like a main service, even though it is a subpanel; you may only do this in a detached structure with no bonded metallic paths between the structures.
In either case you must have the ground rods.
I was confused by something: was this a 120V or a 240V subpanel? You describe three wires (2 #6 and 1#8); which is hot, which is ground, and which is neutral?
-Jon
#7
2 #6 and 1 #8.. so thats the 2 hot and the ground. What did you run for the neutral?
You need to install a ground rod,a ground bar, move all the grounds to the ground bar and remove the bonding screw. Hopefully you do all that with the breaker off in the house
You need to install a ground rod,a ground bar, move all the grounds to the ground bar and remove the bonding screw. Hopefully you do all that with the breaker off in the house
