Detached Sub Panel

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Army Mike

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First, I DO NOT want to start a one up battle of the minds. Lots of smart minds here I'm sure that's hazed with different opinions, haha.

Facts:
I purchased my home with a detached workshop 200' from main house located outside of city limits in Tennessee.
Built 2007.... I did not build any of it!
100A panel in the shop wired straight to the main home panel to a 50A CB I believe.
NO gas, telephone, water, sewer, cable, no overhead structures...etc. Just power wires from shop to home main.
Direct buried (aluminum) feeder wires (no conduit)......3 aluminum wires total. 2 hot and a neutral. No dedicated ground back to home main.
Also, No ground rod is installed at shop.. anywhere??
I didn't install it, bury, modify, repair, or approve this set up, so please go easy on me.

This shop sub panel has neutral/ground bonded and No green neutral bonding screw that I can tell.
I have 120V and 240V equipment in the shop that I use.

I have read (250.32) current code and understand 3 conductors, one ground is the rule...4 wires.

I can't run all new wire at the moment, and for sure cant snake a ground back to the house.

I just want to know if this the "safest" set up possible (in this situation?)

Is this is acceptable under the (old way) until I can afford to update the wire.

The ONLY reason I noticed this is because I had to install an additional CB in my shop panel for a new light and was like :blink:Hmmmm???

Thanks in advance and I hope I have provided enough information.

Mike:D


 
welcome to the forum.

Your install was very likely compliant when it was installed except for the fact that you are missing a ground rod at the detached structure. I would not worry too much but I would probably get some rods installed.
 
I Agree with Dennis, sounds fine. If it were my house, i would put the ground rods on the list, but probably never get to them :angel:. I just wasn't totally clear on this part:


"This shop sub panel has neutral/ground bonded and No green neutral bonding screw that I can tell."

Are the neutral and egc bars bonded with a wire, or on the same bus? You still need to bond the cabinet.
 
I can't recall when TN adopted the '08 but if your structure was build in 2007 it was likely a legal install then. I concur with others,, establish a grounding electrode and worry not.
 
electrofelon said:
I Agree with Dennis, sounds fine. If it were my house, i would put the ground rods on the list, but probably never get to them :angel:. I just wasn't totally clear on this part:


"This shop sub panel has neutral/ground bonded and No green neutral bonding screw that I can tell."

Are the neutral and egc bars bonded with a wire, or on the same bus? You still need to bond the cabinet.
Click to expand...


Sorry, yes on same bus, just no screw to bond through to the metal cabinet.

Thx.
 
Adamjamma said:
Wonder if the grounding electrode was in the slab foundation pour? UFER? May be there and he does not see it?
Click to expand...


Hi, that may be possible and will double check. The unfortunate issue is I know who built this shop and the workmanship was subpar. I’m almost certain there isn’t even rebar/wire in the slab...not even a vapor barrier was installed. Its a 30x30 shop built out in the country. Wood, and vinyl siding, shingle roof. Not horrible by any stretch but not even close to my standards. I think it was “let’s get it done project.”Haha

Thx ,
Mike
 
Army Mike said:
First, I DO NOT want to start a one up battle of the minds. Lots of smart minds here I'm sure that's hazed with different opinions, haha.

Facts:
I purchased my home with a detached workshop 200' from main house located outside of city limits in Tennessee.
Built 2007.... I did not build any of it!
100A panel in the shop wired straight to the main home panel to a 50A CB I believe.
NO gas, telephone, water, sewer, cable, no overhead structures...etc. Just power wires from shop to home main.
Direct buried (aluminum) feeder wires (no conduit)......3 aluminum wires total. 2 hot and a neutral. No dedicated ground back to home main.
Also, No ground rod is installed at shop.. anywhere??
I didn't install it, bury, modify, repair, or approve this set up, so please go easy on me.

This shop sub panel has neutral/ground bonded and No green neutral bonding screw that I can tell.
I have 120V and 240V equipment in the shop that I use.

I have read (250.32) current code and understand 3 conductors, one ground is the rule...4 wires.

I can't run all new wire at the moment, and for sure cant snake a ground back to the house.

I just want to know if this the "safest" set up possible (in this situation?)

Is this is acceptable under the (old way) until I can afford to update the wire.

The ONLY reason I noticed this is because I had to install an additional CB in my shop panel for a new light and was like :blink:Hmmmm???

Thanks in advance and I hope I have provided enough information.

Mike:D
Click to expand...


Are you stating the grounds and neutrals are installed on the same ground bar/neutral bar? If so, Its a violation since it’s a sub panel.
 
lordofthisworld said:
Are you stating the grounds and neutrals are installed on the same ground bar/neutral bar? If so, Its a violation since it’s a sub panel.
Click to expand...
As pointed out in Post #2 and #5....
It was not a automatic violation if the sub-panel was located in a detached building until, I believe, the '08 Code.
If his install was prior to TN adopting the -08, the neutrals & equipment grounds could possibly share the same bar.
 
Here is another picture. Also, there actually isn’t a beaker an “independent” breaker at the main home panel for the feeder line down to the shop, only a 100A at the shop sub and a 225A on the home. I’ll post a picture of that weirdness as well. As stated before, I didn’t do any of this, it’s how I purchased the home and the shop. Those 2 wires bolted down right under the 225A run straight to the shop sub.
 

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In regard to your house panel.. there are a couple of violations.. the method of tapping is altering a piece of UL equipment but far more importantly the conductors to the shop are not properly protected. Ideally they should have been connected to a breaker in the panel.
 
Mike I am closing this thread because it is clear you are not properly trained for this work. Forum rules do not allow us to help with diy questions and this is clearly a diy job. I suggest you call a professional electrician in to take care of these issues.
 
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