EGC of subpanel

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floater4444

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I have a 200amp panel going to a 100A subpanel. I have the 200A EGC as a #4 copper going to the Ufer. The water comes up right by the subpanel and instead of running a #4 all the way from the original panel, can I bond the subpanel to the water and that would take care of the EGC from the main 200 amp panel?
 
floater4444 said:
I have a 200amp panel going to a 100A subpanel. I have the 200A EGC as a #4 copper going to the Ufer. The water comes up right by the subpanel and instead of running a #4 all the way from the original panel, can I bond the subpanel to the water and that would take care of the EGC from the main 200 amp panel?
Click to expand...


In 05 NEC You we're allowed tyo run three wires to the sub panel and use a grounding electrode at the sub panel.
In 08 You have got to run the EGC along with the other three. (4 -wires total for single phase)
You still have to isolate the neutral either way. And you still need a grounding electrode at the sub panel. And of course treat the main(s) the same.
 
buckofdurham said:
In 05 NEC You we're allowed tyo run three wires to the sub panel and use a grounding electrode at the sub panel.
In 08 You have got to run the EGC along with the other three. (4 -wires total for single phase)
You still have to isolate the neutral either way. And you still need a grounding electrode at the sub panel. And of course treat the main(s) the same.
Click to expand...

This is true for a separate building/structure, with no other parallel metallic paths

For a sub panel in the same building, you must install an EGC with the feeder.
 
buckofdurham said:
In 05 NEC You we're allowed tyo run three wires to the sub panel and use a grounding electrode at the sub panel.
In 08 You have got to run the EGC along with the other three. (4 -wires total for single phase)
You still have to isolate the neutral either way. And you still need a grounding electrode at the sub panel. And of course treat the main(s) the same.
Click to expand...

So I have to bond the subpanel as well as the main panel to both the ufer and the water?
I do have a 4 wire going from the main panel to the sub and have seperated my grounds and neuts
 
JohnJ0906 said:
This is true for a separate building/structure, with no other parallel metallic paths

For a sub panel in the same building, you must install an EGC with the feeder.
Click to expand...

It's true either way the Equipment ground has to go with it.
Unless of course you have metal conduit that you are useing as the equipment grounding conductor.
But it is still basically the same
 
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buckofdurham said:
In 05 NEC You we're allowed tyo run three wires to the sub panel and use a grounding electrode at the sub panel.
In 08 You have got to run the EGC along with the other three. (4 -wires total for single phase)
You still have to isolate the neutral either way. And you still need a grounding electrode at the sub panel. And of course treat the main(s) the same.
Click to expand...

I did run a 3 wire + ground from the 200A main to the 100A sub and seperated my grounds and neuts.

Are you saying that I have to bond my sub as well as my main to both the ufer and the water?
 
I have a 4 wire feeding my 100A subpanel as well as seperating my grounds and neuts. Are you saying that I have to bond my sub as well as my main panel to both the ufer and the water?
 
right now, I just have the main panel to the ufer and was gonna bond the sub to the water, thus having the water bond travel through the sub feeder back to the main. Will that not fly though with the code?
 
floater4444 said:
I have a 200amp panel going to a 100A subpanel. I have the 200A EGC as a #4 copper going to the Ufer. The water comes up right by the subpanel and instead of running a #4 all the way from the original panel, can I bond the subpanel to the water and that would take care of the EGC from the main 200 amp panel?
Click to expand...

Floater, are these panels in the same building?
 
JohnJ0906 said:
Floater, are these panels in the same building?
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John, are you thinking of useing the buiilding steel for the egc ?

I don't think you can do that any more.

But if the panel is in the same building you don't need an other grounding electrode or a main
 
buckofdurham said:
It's true either way the Equipment ground has to go with it.
Unless of course you have metal conduit that you are useing as the equipment grounding conductor.
But it is still basically the same
Click to expand...
it is a pvc conduit under concrete. I have a bonding bushing on the main panel side and the other side is just open into a stud bay. I don't have to use any type of connector on that side to go into a stud right?
 
buckofdurham said:
John, are you thinking of useing the buiilding steel for the egc ?

I don't think you can do that any more.

But if the panel is in the same building you don't need an other grounding electrode or a main
Click to expand...
The water is right by the subpanel and there was one existing ground rod that is now in the garage. I have connected both of them into the subpanel. I was wondering if I can use the feeder that is going from the main panel to the sub as a way to bond the water to the main panel. There is no gas in the house so I don't need to worry about that
 
Floater, you will need to add an EGC for that 100 amp now-a-sub panel. Also, you will have to separate the EGCs in that panel from the neutrals, and remove the bonding jumper.
No connection to a grounding electrode is necessary. That should be done at the new service entrance.
 
floater4444 said:
The water is right by the subpanel and there was one existing ground rod that is now in the garage. I have connected both of them into the subpanel. I was wondering if I can use the feeder that is going from the main panel to the sub as a way to bond the water to the main panel. There is no gas in the house so I don't need to worry about that
Click to expand...

No you can't do that.
 
JohnJ0906 said:
Floater, you will need to add an EGC for that 100 amp now-a-sub panel. Also, you will have to separate the EGCs in that panel from the neutrals, and remove the bonding jumper.
No connection to a grounding electrode is necessary. That should be done at the new service entrance.
Click to expand...
So i have ran an EGC to the water for the 100A subpanel. I have seperated the grounds and neutrals. There is no bonding jumper in the sub. It is being fed by a 100Amp breaker in the main panel.

I don't really want to run a 100' #4 back to the water from the main panel and was wondering if I could bond the water from the sub panel back through the feeder to the main panel
 
buckofdurham said:
No you can't do that.
Click to expand...


The water line ground has to go directly to the main.
To clear a ground fault the electricity will take the quickest path to ground. You don't want it traveling through your sub panel.
The water line is ussually a better ground, too. then the ufer. So it would definetly be used in a ground fault situation.
 
buckofdurham said:
No you can't do that.
Click to expand...
ok, so I have to run the #4 from the main to the water entering the house. It is 100' so I just wanted to make sure I couldn't save a couple bucks by using the main ground feeding the sub to bring it back to the service panel
 
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