Did a house last Sat ( 2/28 ) in Minneapolis. Overhead service entrance from street going to detached garage. 1920’s house has updated elec done around 2001. 200amp main in garage, everything looked good had a driven ground rod outside by meter. 100amp breaker going to house on underground feed. Get into house figuring to finish off sub panel in basement. Pull cover and it looks like another Distribution panel, neutrals & grounds together, no floating bus bar, bonding screw turned in. ( also had a non terminated wire ) Be cause it was a newer upgrade with stickers of approval from 2001 I figured I must have missed something. House had a cold water ground. My question, the house ( 100amp ) was wrong, right? It all looked so new and nice I hated to call it out but I did. Also should house have had a driven rod to go along with cold water grounding? I did talk to some elec “experts” and they said no big deal with the house panel. I including some pics, I hope they come through so you can see. 200amp in garage is pretty empty with only garage circuits on it.
thanks for any help, Mark T
One of these was an improperly wired subpanel.
It doesn’t matter what it “looks” like, it matters where it’s “located” with respect to the service entrance. The service equipment is the first disconnect after the entrance.
As James said, one of the panels is wired wrong. . .
It depends. He says the house is detached from the garage. Up until the 2008 NEC a 3-wire feeder was perfectly legal to a detached structure with some stipulations. One being no other metallic paths between buildings, such as a water pipe or CATV/ph wires.
If the phone and cable do not hit the garage first and then on to the house it is most likely compliant and safe.
Without knowing more about it this could be a perfectly fine installation.
The only thing I can see is that a detached structure does require a grounding electrode. Even if the water pipe was used as an electrode it still needs a supplemental electrode.
Thanks guys, the photo far left is the service entrance from street into garage. The two photos on right is the downstream 100amp house distribution panel being fed from the 200amp garage sevice panel. Thats what I thought, I couldn’t get on message board Sat to run this by some of you guys. Mark T
Dont forget to mention the grounds and nuetrals together on the same screw
Thanks Speedy, (I appreciate that you are still here helping us out)…that’s what I was remembering but typically it is difficult to verify if there is any potential between the buildings so I usually defer to a qualified electrician.