Service panel bonding to ground

[Al D. Bolt]

Can anyone show me where or how this service panel is bonded to ground?
Thanks.

[Paul W. Abernathy]

Hey fella........it appears there is a 4 AWG or 6 AWG on the lower right side of the grounded/grounding buss. That could be your grounding to a Ufer if 4 AWG oe Rods if 6 AWG.... Now i am answering this on my motorola Q phone so i cant see it real well....

1) Did you check to make sure a bonding jumper was installed...either by screw or strap...i just cant see the image well.

2) always remember in your main service panel look for that enclosure bond....and check the bare conductors and their size.......look for connections for a Ufer or Rods at or near the meter outside.

FYI - it looks like the main bonding jumper is missing........grounding may be present but the isue may be the bonding of the enclosure .

[David P. Valley]

Paul is referring to this solid #6 AWG.

"Click To Enlarge"


Did you check at the water main?

[Speedy Petey]

The bond screw is missing. It goes in that empty hole just to the right of the right hand service conductor.

There could be another bond wire connected to the panel somewhere, but I can't see it and it would not be a factory bond.

[Paul W. Abernathy]

Originally Posted by dvalley

Paul is referring to this solid #6 AWG.

"Click To Enlarge"
Attachment 16734

Did you check at the water main?

I hope it is not 6 AWG going to the water main David....bein that this looks like a 200A panel...chances are 2/0 CU or 4/0 AL then the size would need to be 4 AWG......so if it is indeed 6 AWG......i would check for Rods....

[Speedy Petey]

That looks like #4 solid to me Paul. Problem is there is only one I can see.
There should be at least two in any case. Even if the water is just a bond and not used as an electrode.
Water/rod. Water/Ufer. Water/steel. Etc.

[David P. Valley]

Originally Posted by pabernathy

I hope it is not 6 AWG going to the water main David....bein that this looks like a 200A panel...chances are 2/0 CU or 4/0 AL then the size would need to be 4 AWG......so if it is indeed 6 AWG......i would check for Rods....

I guess you have to be there to actually figure the size of the ground.

[jtedesco1]

The NEC Defines this as the: "Main Bonding Jumper" or as it appears in NEC Article 100:

"Bonding Jumper, Main. The connection between the grounded circuit conductor and the equipment grounding conductor at the service."

[Paul W. Abernathy]

Agreed fella.....i cant see much on this small 3 inch screen. If only one is present and it is 4 AWG then i would look for a Ufer....if that is present no other is needed unless it is indeed present like Peter said.....then they have to be tied together...

So we have to assume IF the water line coming in is metal.....if not increases the chances it is a Ufer......BUT any electrician who leaves out the bonding screw i begin to question many things....right know we know it is not bonded properly....since that is all we can see on that issue....we are grasping at straws....lol

Need more info from the OP

[Speedy Petey]

Originally Posted by pabernathy

......BUT any electrician who leaves out the bonding screw i begin to question many things....right know we know it is not bonded properly....since that is all we can see on that issue....we are grasping at straws....lol

Good point!


The only thing I could see is if the installer used #4 and went right from the water bond to a rod with the same #4. Unconventional but legal.

[Paul W. Abernathy]

very true Peter......there are many possible concepts....he/she could run 4 AWG to the water main piping....then go from it ( within 5 ' of entrance ) to a set of ground rods with 6 AWG we just dont see here....nothing says it has to come back to the panel shown...so we can thin of many ways........guess they are all assuming right now but YES it does concern me that no bonding jumper is present.........we think alike fella.....Thats a GOOD thing....

[Paul W. Abernathy]

Keep in mind......if it is a Ufer as far as the grounding goes....you would only see one as supplimentals are not required for CEE .....

So it really depends on whats present.....if metal water piping in earth....yes needs a suppliment electrode...if not metal and only a CEE is used then only (1) 4 Awg would be needed.

This makes it soooo hard for electrical guys like Me, Peter, Joe, Greg and other electrical guys to guess without all the factors present.

[Al D. Bolt]

That solid #6 AWG goes to a grounding rod.
In reference to the mentioned missing bond screw on the right:
1) this screw is supposed to go through to the panel box?
2) since there is a tie bar present, wouldn't the bond screw on the left suffice?

[Greg Fretwell]

You could also have the GEC coming out of the meter base, very popular here.

[Speedy Petey]

1) this screw is supposed to go through to the panel box?
Yes.

2) since there is a tie bar present, wouldn't the bond screw on the left suffice?
That silver screw to the left is not a bond screw. It does not go through into the back box.