Grounding Tank

E

Electrobe

Member

• Nov 10, 2009

• #1

We have an outside metal tank that has a 110V, 20A circuit feeding the tank heater. Does the tank need to have a separate ground conductor ran from the plant ground-grid to the tank or can the the ground conductor ran with the power be used to bond to the tank?? The ground-grid is bare 4/0.

Thanks

 

P

petersonra

Senior Member

Location

Northern illinois

Occupation

engineer

• Nov 10, 2009

• #2

I think the ground wire you are running with it is adequate, short of some information you have left out.

is there by any chance metal water piping involved?

 

Last edited: Nov 10, 2009

E

Electrobe

Member

• Nov 10, 2009

• #3

petersonra said:

I think the ground wire you are running with it is adequate, short of some information you have left out.

is there by any chance metal water piping involved?

Click to expand...

I think the piping going to the tank is metal. Could I use the piping as the grounding conductor? Assuming it is grounded correctly.

Any other info I left out?

Thanks

 

I

IllinoisElectrician

Member

• Nov 10, 2009

• #4

Refer to 240.118, yes you can use the pipe as your ground path provided it meets all the requirements. (EMT, IMC, RMC, and no more than 6 feet of flex in the path). If it has the green wire, directly to the metal box using a green screw is adaquate.

 

E

Electrobe

Member

• Nov 11, 2009

• #5

Is there other codes that require this tank to be grounded to the plant ground grid since it is located outside (maybe for lightning, static, or potential equalizing)? Many of the other tanks in the plant are connected to the ground-grid with a 4/0 bare conductor.

Is so, how do you determine the size of the ground conductor??

Thanks

 

P

petersonra

Senior Member

Location

Northern illinois

Occupation

engineer

• Nov 11, 2009

• #6

Electrobe said:

I think the piping going to the tank is metal. Could I use the piping as the grounding conductor? Assuming it is grounded correctly.

Any other info I left out?

Thanks

Click to expand...

take a look at 250.104.

 

erickench

Senior Member

Location

Brooklyn, NY

• Nov 11, 2009

• #7

If the connecting pipe were a water pipe it can be used as a grounding electrode if it's in contact with the earth for a minimum of 10 feet. It is also a part that is likely to become energized so you would have to bond it. It must be connected to the other grounding electrodes i.e. structure etc. This could provide and fault current return path back to the service. If it's a gas pipe then you cannot bond it.