Electrical panel- no ground

[Tim Schoenhals]

Hello,

I just moved my shop to a new location here in sunny North Hollywood CA and was looking over the electrical panel and noticed there is no ground wire coming in from the service entrance. There is a 200 amp main on the outside rear wall and that feeds the inside panel about 30 feet away. Here are pics of both.

I'm wondering if I need to hire someone to come out or if this appears ok. Thanks for any info! My buddies shop just had an electrical fire so super on edge about it!

 

[Cacher_Chick]

I cannot make out the finer details of your panel photo, but it does look like a bare copper conductor entering with the service conductors.

 

[Sponsor]

 

[Tim Schoenhals]

I cannot make out the finer details of your panel photo, but it does look like a bare copper conductor entering with the service conductors.

I just realized that it does look that way. That is actually a pull string that looped up there from another conduit. There are only the 3 large wires coming in there.

 

[JRC3]

Had to have my foreclosure inspected to have the power turned back on because it sat for over a year. He came and told me exactly what to do. Had to bolt a bar in the circuit box to bond the neutral bar ta the box, and bond all the masts ( I have 3 between the house and garage). He also had me plug the knockouts that had been removed just like yours.

What is that next to my red arrow in the pic? Is that a ground? Looks small if it is. I would have the inspector come out and tell you what to do. I think it cost me 40 or 60 bucks.


Edit: I guess never mind about my pic.

 

[Tim Schoenhals]

I cannot make out the finer details of your panel photo, but it does look like a bare copper conductor entering with the service conductors.

I just changed the picture for something with better light and I moved that pull string.

 

[Jadnashua]

Is the subpanel 120vac or 240vac? Normally, if it's 240vac, you'd see a minimum of two breakers, or one with ganged levers.

 

[Tim Schoenhals]

Is the subpanel 120vac or 240vac? Normally, if it's 240vac, you'd see a minimum of two breakers, or one with ganged levers.

The panel with one breaker is the main panel with the service entrance. Each leg is 120v and the one with the white stripe is neutral.

 

[Bluebinky]

No a pro... It's not quite right, but doesn't look super dangerous to me. It should be fixed, though.

Is JW still arround? He has the authority to explain exactly what to do...

 

[Tim Schoenhals]

After looking a little closer, the neutral bar and the bar that has the grounds on it are connected together through that black horizontal bar and both are isolated from the panel. There is continuity between the neutral and the box.... i guess because they are bonded at the main panel.

 

[JRC3]

The box needs bonded. If the neutral is lost then the box could potentially become hot without tripping the main breaker or even anything at the pole or transformer. Same with a mast or anything metal the service runs through that isn't connected to the earth. I may not be 100% correct on my description and terminology but I'm pretty sure that's the gist of it.

 

[Stuff]

If it is metal conduit from the disconnect box to the panel it counts as a grounding connector so you don't need a separate wire.

The ground and neutral bars need to be separate as it is not a service panel. The label on the panel door should explain either how to separate the two bars (and bond one to the cabinet) or to add a separate grounding bar.

In addition to filling the open holes it is also missing grounding bushings if it is metal conduit on the main feeder.

 

[Tim Schoenhals]

If it is metal conduit from the disconnect box to the panel it counts as a grounding connector so you don't need a separate wire.

The ground and neutral bars need to be separate as it is not a service panel. The label on the panel door should explain either how to separate the two bars (and bond one to the cabinet) or to add a separate grounding bar.

In addition to filling the open holes it is also missing grounding bushings if it is metal conduit on the main feeder.

Yes, there is metal conduit that runs on the roof between the disconnect box and the panel. So would the grounding bushing need to go on the opening from the conduit from the disconnect panel?

Thanks for the replies everyone. I think I'm starting to understand what it needs. I think I also learned that there are too many circuits in the conduit just to the right of the service entrance. Is it true that the max is 4 circuits unless it's under 24"?

 

[JRC3]

If it is metal conduit from the disconnect box to the panel it counts as a grounding connector so you don't need a separate wire.

But what if an event separated the conduit but the service wires stayed intact? =No gounding. Again, I'm no pro, but after talking to inspectors I think they want a large subs like that grounded to the earth. I have a 100A sub that is bonded at the bus bar. He made me ground the box directly to that bus with a ground attached with a 1/4" bolt directly to the metal breaker box.

 

[Stuff]

Sorry, I jumped the gun on the bonding bushing. Since the conduit is for a feeder and not service wires it is not required.

There is no maximum number of circuits in conduit. There is a maximum number of wires for each size of conduit. 9 in a 1/2 pipe with 12 awg. And if you have more than 6 current carrying conductors you have to derate the ampacity. Usually need to up the wire size or use smaller breaker.

 

[Jadnashua]

A main, entrance panel has the ground and neutral wires bonded together along with the box to ground...a subpanel should have four conductors and the ground and neutral busses are supposed to be isolated. The subpanel box is grounded, but it is isolated from neutral there so you don't have parallel paths for the current (only together at the main panel). The ground wire should never have current except in a fault situation.

 

[Stuff]

But what if

Codes account for a lot of what ifs. Worrying that the conduit fails to be electrically conductive end to end is not one of them.

 

[JRC3]

Codes account for a lot of what ifs. Worrying that the conduit fails to be electrically conductive end to end is not one of them.

But as the only bond? Not according to my inspector. His description, at least on my masts, if the neutral becomes unattached further ahead and a hot comes in contact after, then the mast/conduit can become live and unprotected. Then a human touching it becomes the bond. Same thing inside the breaker box, if the bus bar was the only thing grounded and it came loose, and then you contacted the box, then the grounding to the breaker box would provide redundancy.

Keep in mind that I'm talking about old existing work of 1984 and prior. I don't think it matters. This was fall of 2015 when the inspector's direction took place.

 

[Stuff]

It sounds like your inspector was making his own rules. Not unheard of. You should always respectfully ask for a code reference - tell them you are trying to learn and will read the whole section to better understand and see if there is anything else you could be missing for other work.

 

[Bluebinky]

If it is metal conduit from the disconnect box to the panel it counts as a grounding connector so you don't need a separate wire.

It looks like the conduit leaving the disconnect is surrounded by a knockout ring. To use the conduit as a grounding conductor, a "bonding jumper" will be needed. It's hard to see if it's the same in the subpanel.

In the subpanel you'll still need a main disconnect, isolated neutrals, the ground bar bonded, and the holes filled (at a minimum).