To bond or not to bond, that is the question...

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seiser3

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Hi all,

A new member to this forum, but long time scroller. I am looking for some guidance on bonding a panel.

We bought a home that was built in 88'. We will be replacing an outdoor main disconnect, with one that has spaces for breakers for a future outdoor sub-panel. Anywhoo, we have two points of disconnect for our indoor panel. The first point of disconnect is the outdoor main breaker, and a main breaker residing within our indoor panel. There is a single grounding rod with bare copper that lands in the meter can where it is bonded to neutral. The disconnect and meter can are metal and mounted together. There is a 3 wire service (hot,hot,neutral) that runs via PVC from the disconnect to indoor panel (no ground). The indoor panel is bonded to the neutral (shared bus bar) with no dedicated ground.

Question: Is this normal? Maybe code was different in the 80's, but I thought you should not have a bonded panel after the first point of disconnect. I have attached some photos. The electrician who has serviced the panel said this is a normal three wire service, but I have not been able to corroborate this via the NEC or via other forum posts. Any info helps! Still learning. From a theory perspective, I suppose that as long as the ground are bonded to Neutral, that any ground faults would find there way back to source from the outdoor main breaker.

Thanks,
Zach
 

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Eddie_T

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GFIs determine ground faults by comparing supply and return current, not by actually measuring current to ground so you should be OK. Mine is grounded from the meter and the panel is grounded inside to a water pipe. I don't know if that is correct with current code.
 

seiser3

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Thanks, Eddie. I guess I am also curious about ESD and lightning, if this setup could affect proper operation of earth ground.
 

kok328

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I've seen this setup once before and had the same first impression.
In my opinion, any panel after the first disconnect should be treated as a sub-panel and not be sharing a neutral bar. I also would have expected to see a ground wire ran with the 3-wire feed.
This was in a manufactured home. Don't know if the solar changes anything.
 

ajaynejr

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Under the most recent code (actually for several decades now) the first disconnect location, which may be under the meter, is the "main panel" and separate ground and neutral must continue from there to everything including to a large basement panel you may have referred to as the "main panel".

If the conduit carrying the feed wires from the meter to the basement panel is all metal then that can be the grounding means (equipment grounding conductor.

... opinion, any panel after the first disconnect should be treated as a sub-panel ...
Fact: any panel after the first disconnect must (shall) be treated as a sub-panel

There are still a few grandfathered 3 wire 120/240 volt and 2 wire 120 volt (no ground) feeds from a house to a subpanel in a detached garage or other outbuilding. Ground wires (equipment grounding conductors) may not be combined with the neutral to go back to the main house.
 
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afjes_2016

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seiser3 - Because this is electrical service for a built in swimming pool it may require an entire different type of bonding system than normal main/sub panel. The swimming pool needs to be bonded specially to prevent electrocution. I am not up to date with the proper bonding methods for a built in swimming pool and normally this type of electrical bonding is performed by an electrician specially trained and educated in these proper bonding techniques. If I were you I would contact a pool store/company in your area and get the contact information of the electrician they use for their installations and then consult him/her.

I retired as a certified, licensed and insured electrician that went to school for the trade for several years. Even with this education and years experience I would not touch the bonding of a built in swimming pool because of my lack of specific knowledge of the proper bonding method. I have turned down jobs for built in swimming pools, above ground pools and even some outdoor hot tubs for this reason.
 

seiser3

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seiser3 - Because this is electrical service for a built in swimming pool it may require an entire different type of bonding system than normal main/sub panel. The swimming pool needs to be bonded specially to prevent electrocution. I am not up to date with the proper bonding methods for a built in swimming pool and normally this type of electrical bonding is performed by an electrician specially trained and educated in these proper bonding techniques. If I were you I would contact a pool store/company in your area and get the contact information of the electrician they use for their installations and then consult him/her.

I retired as a certified, licensed and insured electrician that went to school for the trade for several years. Even with this education and years experience I would not touch the bonding of a built in swimming pool because of my lack of specific knowledge of the proper bonding method. I have turned down jobs for built in swimming pools, above ground pools and even some outdoor hot tubs for this reason.
Thanks for the info. The PV array is actually a backfeed to the utility, not tied in with the pool. It has its own subpanel.
 

billshack

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I recently got a generator. and i wired up a 4 plex outlet splitting the 240 volts so that i had lots of power from both sides
1612197599245.png

In the instruction it talked about a floating neutral vs a bonded neutral .
I did not know what to do , so i called a friend that is an electrical engineer . He said it makes no difference in this case ,
 

afjes_2016

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I recently got a generator. and i wired up a 4 plex outlet splitting the 240 volts so that i had lots of power from both sides...
I am sorry billshack but I don't know what this has to do with the OPs post? Did you in error post in the wrong thread?

Also you stated
..so that i had lots of power from both sides ..
Don't quite know what you are referring to here. Splitting up 240v does not give you more power from your generator. The generator is rated at a specific watts start up and run. Providing dual duplex receptacles is not going to provide more "power".
 

Eddie_T

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Maybe more usable power as one could max out both legs rather than overloading one leg.
 

afjes_2016

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Maybe more usable power as one could max out both legs rather than overloading one leg.
I'm sorry but I still don't see how this setup will provide more usable "power" (watts) than the generator is rated at either at startup or run time.
 

Eddie_T

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I'm sorry but I still don't see how this setup will provide more usable "power" (watts) than the generator is rated at either at startup or run time.
You're right but doesn't loading only one winding limit one to ½ the generator's rated capability?
 

billshack

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I am sorry billshack but I don't know what this has to do with the OPs post? Did you in error post in the wrong thread?

Also you stated

Don't quite know what you are referring to here. Splitting up 240v does not give you more power from your generator. The generator is rated at a specific watts start up and run. Providing dual duplex receptacles is not going to provide more "power".
you did not understand what i was talking about. my generator provides 240 volts. so by splitting the the two hot leads i end up with 120 volt one one side and 120 volts on the other. by doing this i can use both 120 volts with out overloading any one side . when you do this do you float the neutral or bond it to the ground.
 

Ron Van

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you did not understand what i was talking about. my generator provides 240 volts. so by splitting the the two hot leads i end up with 120 volt one one side and 120 volts on the other. by doing this i can use both 120 volts with out overloading any one side . when you do this do you float the neutral or bond it to the ground.
If you are just plugging appliances or tools into your 4plex outlet then you want to bond your generator's neutral to the generator's ground (or frame -which is the ground). If you are connecting your generator to your house's electrical system (or shop, garage, etc) then you disconnect the generator's neutral from the ground (or frame) and use a floating neutral on your generator. The neutral bonding in this case should happen at the first place of disconnect which normally is the main breaker.

The idea is that the neutral should only be bonded once in the system and close to the first disconnect. If your generator is bonded more than once, the GFI on the generator will not like it and constantly trip.
 

afjes_2016

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billshack it seems we have hijacked the original poster's thread without realizing it.

Sorry seiser3. Was not intentional.

billshack I think it best that any further discussions about your situation that you post a new thread to prevent confusion.
 

billshack

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billshack it seems we have hijacked the original poster's thread without realizing it.

Sorry seiser3. Was not intentional.

billshack I think it best that any further discussions about your situation that you post a new thread to prevent confusion.
O K
 

Eddie_T

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Wasn't the OP's question answered? Most threads tend to waft on and drift a bit after every has put their initial 2¢ in.
 
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