Grounding and Bonding

[Tlogix]

I have a Meeter then a Main disconnect about 300 feet from the building its feeding. I have a main panel inside the building 4 wires running from the disconnect to the main 3 hot one neutral.
I have ground rods at both, main disconnect and main panel.
Can I just bond the neutral to the ground at the main panel?
Or do I need to run a ground wire between the 2 panels?

Example:
Five wires three hot one neutral one ground.
120/208

 

[don_resqcapt19]

You need an equipment grounding conductor (WGC) between the service disconnect and the main panel in the building. You also need grounding electrodes at both locations, but the grounding electrode conductor (GEC) is connected to the neutral only at the service disconnect. The GEC at the building panel is connected to the EGC, but is not connected to the neutral.

You say that the main panel is inside the building. That panel has to be "nearest the point of entrance" of the feeder conductors per 225.32.

 

[Tlogix]

I have attached a PDF of the setup.
The wires are USE not in conduit From Main Fused disconnect to Panel boards.

 

[don_resqcapt19]

I have attached a PDF of the setup.
The wires are USE not in conduit From Main Fused disconnect to Panel boards.

That is not compliant with current code rules. Your cables between the service disconnect and the building panels need to include an EGC.

If this is an older existing installation, it may be compliant, but it is not compliant starting with the 2008 code.

Also there may be issues with rules in 240.21(B) if there is only a single main overcurrent protective device.

 

[Tlogix]

That is not compliant with current code rules. Your cables between the service disconnect and the building panels need to include an EGC.

If this is an older existing installation, it may be compliant, but it is not compliant starting with the 2008 code.

Also there may be issues with rules in 240.21(B) if there is only a single main overcurrent protective device.

Exception No. 1 Would be allowing disconnection to be elsewhere on the premises.

As for the individual protection for multiple panel boards has never been a question with the inspector its the second job in the last year that has been installed this way that I have seen.
But no EGC between the disconnect and panel on both jobs Thats why Im wondering what the requirements are I was told to remove the bond between the neutral and the ground on both jobs at the panel boards.
I don't feel like the ground between the disconnect and the panel boards is good enough for a ground path.
In these cases wouldn't it be better for the neutral to be bonded at the panel boards?
Or have a EGC dug in and connected to disconnect and panel boards.

 

[jumper]

Exception No. 1 Would be allowing disconnection to be elsewhere on the premises.

As for the individual protection for multiple panel boards has never been a question with the inspector its the second job in the last year that has been installed this way that I have seen.
But no EGC between the disconnect and panel on both jobs Thats why Im wondering what the requirements are I was told to remove the bond between the neutral and the ground on both jobs at the panel boards.
I don't feel like the ground between the disconnect and the panel boards is good enough for a ground path.
In these cases wouldn't it be better for the neutral to be bonded at the panel boards?
Or have a EGC dug in and connected to disconnect and panel boards.

I had to get rid of the screwy font and type size to read this. The fancy writing is hard for old folks to see.

 

[don_resqcapt19]

Exception No. 1 Would be allowing disconnection to be elsewhere on the premises.

It would be rare for the AHJ to permit that exception for other than industrial type locations. It would not be accepted by me for any location that does not have full time electrical maintenance on site.

As for the individual protection for multiple panel boards has never been a question with the inspector its the second job in the last year that has been installed this way that I have seen.

Are you saying the building panels do not have mains? Are there one or two breakers at the service disconnect that is located at the meter?

But no EGC between the disconnect and panel on both jobs Thats why Im wondering what the requirements are I was told to remove the bond between the neutral and the ground on both jobs at the panel boards.

If this is a new installation, you would have to install the code required EGC if I was inspecting the job.

I don't feel like the ground between the disconnect and the panel boards is good enough for a ground path.
In these cases wouldn't it be better for the neutral to be bonded at the panel boards?

The path via the earth will not clear faults and is dangerous. It would be better to have the bond, but again if this is a new installation it gets a "do not connect power" tag from me.

Or have a EGC dug in and connected to disconnect and panel boards.

I would accept that as being code compliant.



[/QUOTE]

 

[Tlogix]

There is one main fused Disconnect for both panels plus they both have there own Main Breaker.

I will be putting the jumper back in till the wire can be run from the main to the panels.

 

[don_resqcapt19]

There is one main fused Disconnect for both panels plus they both have there own Main Breaker.

I will be putting the jumper back in till the wire can be run from the main to the panels.

So that still leaves open the question of the rules found in 240.21(B) for the conductors between the service disconnect and the two panels.

I would also like to know where the panels are in the building in relationship to the point where the feeder conductors enter the building.

 

[Tlogix]

So that still leaves open the question of the rules found in 240.21(B) for the conductors between the service disconnect and the two panels.

I would also like to know where the panels are in the building in relationship to the point where the feeder conductors enter the building.

They are mounted on a exterior wall.
The feeder wires are about 3' long coming true the concrete floor right into the bottom of the panels.