Subpanel question

[alan camby]

Just sold (Pending status) my house and bought a new, to me, place with a 27'x76' pole barn.


Anyhow, had a inspection of my old place and the owners, due to inspection, have asked me to have a licensed electrician look at the subpanel.

I have a small 100 amp subpanel feed by a 100 amp breaker off of the main 200amp panel.
The sub is a old Murry panel located in a room addition to the house and was here when I bougth the home 10 years ago. The panel has two ground/neutral bars stacked on top of each other. The inspector wanted the ground and neutral bars moved. One on the left and one on the right of the breakers. Every panel I have seen has had the two seperate bars connected with a large wire to join the ground and neutral bars on both side of the breakers. So what is wrong with the two bars together in the current location?

 

[pattenp]

Newer code requires the sub-panel to be wired with 4 conductors from the main service panel. The sub-panel should have the grounds and neutrals on separate bars with the neutrals isolated (not grounded to panel). The only place the grounds and neutral are bonded or can be placed on the same or connected bars is in the main service panel. I assume in your case there is a 4 wire connection to your sub-panel from the main panel which should be 2 hots, 1 neutral, and 1 ground.

 

[soapii]

I believe current code is separate ground and neutral. I built my garage last year and the subpanel I bought had the neutral on right and ground on left. I passed my electrical inspection.

EDIT......pattenp beat me to the punch.

--Joe

 

[alan camby]

Newer code requires the sub-panel to be wired with 4 conductors from the main service panel. The sub-panel should have the grounds and neutrals on separate bars with the neutrals isolated (not grounded to panel) from the grounds. The only place the grounds and neutral are bonded or can be placed on the same or connected bars is in the main service panel. I assume in your case there is a 4 wire connection to your sub-panel from the main panel which should be 2 hots, 1 neutral, and 1 ground.

Yes I have 2 hots, 1 neutral and a bare ground in the cable to the sub.
The neutral and the ground are both going to the two connected bars in the picture. The braided bare ground was untwisted for two slots on the bar, assuming this was done to get the large wire to fit in the small holes. You can see these two grounds in the center of the pic. The neutral is connected to a large mechanical lug at the top of the bar.

So can this be done in the current panel or would a new panel be needed. Are these insulated bars and grounded bars available at home improvement store like Lowes and Manards?

 

[djb2]

That could possibly have met code when it was installed.
But bonding the neutral and ground certainly doesn't meet code as a sub-panel.

My guess is that this was once the main panel, and a new 200 amp service was installed with a new panel. The work probably wasn't inspected at that point, or this would have been caught.

This is a significant issue rather than a trivial one. The buyers can back out of the deal unless it is fixed. Nominally it should be at your cost, although the actual result depends on the details of the contract and the local real estate market.

 

[theoldwizard1]

"Current code ..."

Was that code when it was installed ? Likely, yes. You should not have to "fix" something that is not broken just because words on paper changed. It is called "grandfathering".

Besides, I don't see a ground wire coming into the box. Is OP supposed to run one back to the main panel also ?

I would go to the city/county building department and get a copy of the electrical inspection that was done when that sub-panel was installed.

 

[alan camby]

"Current code ..."

Was that code when it was installed ? Likely, yes. You should not have to "fix" something that is not broken just because words on paper changed. It is called "grandfathering".

Besides, I don't see a ground wire coming into the box. Is OP supposed to run one back to the main panel also ?

I would go to the city/county building department and get a copy of the electrical inspection that was done when that sub-panel was installed.

The ground wires from main panel, one braided wire unbraided into two wires, is hole 13 and 14 from the bottom of the top bar.

I doubt the install back in the day was inspected. There is almost no code enforcement in Morgan county Indiana still today.

 

[alan camby]

I have no problem with paying for the repair. I just did not know a subpanel had to have a seperate ground and neutral.

Here is the panel print on the back of the door. There is no place for a main breaker, so assuming that means it was always designed as a subpanel.

 

[Aceman]

Can you post a pic of the whole panel?

 

[Norcal]

Newer code requires the sub-panel to be wired with 4 conductors from the main service panel. The sub-panel should have the grounds and neutrals on separate bars with the neutrals isolated (not grounded to panel). The only place the grounds and neutral are bonded or can be placed on the same or connected bars is in the main service panel. I assume in your case there is a 4 wire connection to your sub-panel from the main panel which should be 2 hots, 1 neutral, and 1 ground.

Been required for a long time it is not a recent development, although in the 60's it was done quite a bit but still wrong.

 

[Charles (in GA)]

Old Square D panels with the "bleacher seat" ground bars were identical. My 40 space Square D panel has the same thing, on both sides. There is NO reason to be relocating the bars, they were most likely designed like that by Murray.

Probably, depending on when the panel was installed, met code with three wires supplying the panel.

I suppose if you want to sell the house, you may have to do some changes, but there is probably no legitimate reason for doing so.

Charles

 

[wyliesdiesels]

Since its a 4-wire feed, it HAS to be corrected!!

I have no problem with paying for the repair. I just did not know a subpanel had to have a seperate ground and neutral.

Here is the panel print on the back of the door. There is no place for a main breaker, so assuming that means it was always designed as a subpanel.

Subpanels located in the same building as the main service do not need a main breaker! However, a panel without a main can have a backfed main breaker installed!

 

[cort]

You didn't post a pic of your entire panel, but it looks like the instructions on your subpanel door tell you that you need to install a separate field installed grounding bar. The diagram shows that a field installed or factory installed ground bar mounts in the left side of the load center. The instructions even give you a model number for the grounding bar depending on the number of holes required.

Having said all this, maybe your Murray panel can be configured a different way than what is described above. It looks like your panel already has 2 bars where the neutrals and grounds land. Carefully inspect the two bus bars on the right of your panel. Is it possible to electrically separate them from each other? Is there a bonding bar, jumper, or screw that electrically connects the two bars? If you can electrically separate the two bars, then it won't be hard at all to bring the subpanel up to code. Remove the bonding jumper or screw. Move all the grounds, including the braided ground wires to the bar that connects to the metal enclosure (right most bar?). Move all the neutrals to the other bar. With the supply neutral temporarily disconnected, use a conductivity tester to be sure the neutral bar is electrically isolated from the outer metal enclosure and grounding bar. Good luck.

 

[FulThrotl]

Just sold (Pending status) my house and bought a new, to me, place with a 27'x76' pole barn.

Anyhow, had a inspection of my old place and the owners, due to inspection, have asked me to have a licensed electrician look at the subpanel.

I have a small 100 amp subpanel feed by a 100 amp breaker off of the main 200amp panel.
The sub is a old Murry panel located in a room addition to the house and was here when I bougth the home 10 years ago. The panel has two ground/neutral bars stacked on top of each other. The inspector wanted the ground and neutral bars moved. One on the left and one on the right of the breakers. Every panel I have seen has had the two seperate bars connected with a large wire to join the ground and neutral bars on both side of the breakers. So what is wrong with the two bars together in the current location?

ok. couple things here. "back in the day" it was common that both ground
wires, and grounded (neutral) wires were landed on the same terminal
strip, which is what you have done here. nothing's gonna burn down or
kill anyone with it done like this.

the code has changed with this, to reflect changes in other portions of
the NEC.

now, you have a separate ground bus for the ground wires, and a
neutral bus isolated from the grounded metal can, for the grounded
(neutral) wires.

i'm assuming that the "inspector" is a private inspector hired to facilitate
the sale of the property, and to limit liability for the real estate agents, etc.

his job is to find some things to fix that don't cost enough money they
kill the sale. if he comes up with something really fugly, and kills the
sale, he'll never get called by that real estate agent again.

and this is what he's come up with.

"The inspector wanted the ground and neutral bars moved.
One on the left and one on the right of the breakers."

my ******** filter is now completely clogged. the man doesn't know
what he's talking about. NOWHERE in the NEC is what he is requesting
required. to perform such a modification on a panel board would change
its UL classification.

he wants the panel code complaint? ok. go down to home desperate,
and buy a ground bus. probably costs about $4.

shut off the panel, lock it off so nobody comes along and turns it back
on and kills someone, and redo the panel. put all the ground wires
on the ground bus, which you have tek screwed to the metal panel can.
leave the grounded wires (neutral wires) on the OEM terminal strip.

while i was at it, i'd clean up the entire panel, so it didn't look so ugly.
lace everything up pretty and straight.

if you are not comfortable with doing this yourself, or don't want the
liability, and there is some, hire a licensed, bonded electrician to do
it for you. under the circumstances, i'd hire someone. then you are
good to go.

and unless the panel busbars are burnt or damaged, don't fall for the
"oh, my, mister wilberforce, you have to replace this panel before the
whole neighborhood burns down" thing.

cost on having that panel gone thru and cleaned up unless you need
a bunch of breakers replaced, should not exceed $350.

 

[theoldwizard1]

Regarding "grandfathering" ...

My BIL caught **** from a home inspector when he was trying to sell his house a couple of years ago because the ground was connected to a close cold water pipe instead of running it back to the meter and clamping it on both sides of the meter. The house was over 25 years old and I am certain it passed inspection back then.

 

[alan camby]

Thanks everyone.
I found a electrician by day sidejob by night guy.
He will be here in the morning to take a look at it and give a estimate.

I feel confident that i could do the work but the buyers insisted on a licenced electrician.

BTW, I saw several ground bars at Lowes that ranged from $5 to $10.

Now my new house has a barn that needs a subpanel. I am looking at a $52 100amp Siemens panel at lowes with a main breaker. From what I have been reading, I need to take one of the neutral/ground bars and isolate it from the panel, remove just a ground screw to make it my dedicated Neutral. Then can i just leave the other bar grounded to the panel and make it my ground?
The barn already has power down there but the current panel has power to all breakers even with the main shut off. My inspector told me that the panel is obsolete (Zinsco brand). Did not check if it had the dedicated neutral and grounds. It is a mess anyhow, Bunch of knockouts punched out with nothing in them and the panel is just plain ugly.

 

[Norcal]

Thanks everyone.
I found a electrician by day sidejob by night guy.
He will be here in the morning to take a look at it and give a estimate.

I feel confident that i could do the work but the buyers insisted on a licenced electrician.

BTW, I saw several ground bars at Lowes that ranged from $5 to $10.

Now my new house has a barn that needs a subpanel. I am looking at a $52 100amp Siemens panel at lowes with a main breaker. From what I have been reading, I need to take one of the neutral/ground bars and isolate it from the panel, remove just a ground screw to make it my dedicated Neutral. Then can i just leave the other bar grounded to the panel and make it my ground?
The barn already has power down there but the current panel has power to all breakers even with the main shut off. My inspector told me that the panel is obsolete (Zinsco brand). Did not check if it had the dedicated neutral and grounds. It is a mess anyhow, Bunch of knockouts punched out with nothing in them and the panel is just plain ugly.

Just buy a ground bar kit, instead of modifying the panel, most of the time when people use one of the neutral bars as a ground bar it's a screw up, & for the few bucks for a GB kit the major problem is taken care of & you can connect the neutrals at either side of the panel.

 

[er3456df]

So, not really on subject, but why are neutral and ground separated?

Are the neutrals coming from the power company not at ground level potential?

 

[alan camby]

So, not really on subject, but why are neutral and ground separated?

Are the neutrals coming from the power company not at ground level potential?

I don't understand why it is needed either. The Neutral and ground are tied together in the main panel, so they should both be of the same potential going into the subpanel.

 

[Aceman]

If they are not separated at the sub then they are in parallel. That means current will split in the sub and be returning to the main panel on both the neutral and ground wires. I shouldn't have to tell you that you don't want any current on your ground wire.

 

[wyliesdiesels]

I don't understand why it is needed either. The Neutral and ground are tied together in the main panel, so they should both be of the same potential going into the subpanel.

If the neutral and grounds are bonded together in the panel and the neutral wire looses its connection, electricity/neutral return current will flow on anything metal that is bonded to the subpanel and main service panel including water and gas lines, metal siding, etc., so it can return to its source, Mr. transformer.

U dont want that happening, so NEC code changed making 4 wire feeds mandatory. Old 3-wire feeds are grandfathered in but CAN become a problem.