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Author	Comments
John Thrash Posted: Mar 26, 2008 10:55 AM	Earth ground Is there an easy way to ground my mobile spray rig? A spike is not always an option.
mason Posted: Mar 26, 2008 11:39 AM	A spike in the ground is the way I was taught. Are there any electricians out there who can help?
John Thrash Posted: Mar 26, 2008 11:41 AM	Also, what is the proper spike length. Is there a drive in the spray foam industry to ground trucks by O.S.H.A.?
Tim O'Keefe Posted: Mar 26, 2008 05:29 PM	Here is how I do it on larger jobs. I run a generator, but have a small sub panel to hook up to a 30amp breaker for shore power (heat in the trailer over night). I run a ground wire from the subpanel to the main panel and utilize the earth ground from the temporary panel at the jobsite. I know I should drive a ground rod everytime I use the machine, but I just haven't bothered so far. I will be doing so in the future as I sure don't want a problem down the road. Hey at least I have an excuse to buy a new hammerdrill to drive the ground rods in. BTW I spoke with an electrician about this and he feels that 1-2 feet would be sufficient for temporary use. Residential code requires 8' but you would be hard pressed to remove that rod and you would never drive it with much success in the winter when the ground is frozen. Tim Granite State Spray Foam Co.
Rob Granger Posted: Mar 26, 2008 08:05 PM	I have a shore cord that has four conductors. Two for hot, one neutral, one ground.. A sub panel always must have seperate neutral and ground bars within.
John Thrash Posted: Mar 27, 2008 09:08 AM	Thanks for the advice.

Author

Comments

John Thrash

Posted: Mar 26, 2008 10:55 AM

Earth ground

Is there an easy way to ground my mobile spray rig? A spike is not always an option.

mason

Posted: Mar 26, 2008 11:39 AM

A spike in the ground is the way I was taught. Are there any electricians out there who can help?

John Thrash

Posted: Mar 26, 2008 11:41 AM

Also, what is the proper spike length. Is there a drive in the spray foam industry to ground trucks by O.S.H.A.?

Tim O'Keefe

Posted: Mar 26, 2008 05:29 PM

Here is how I do it on larger jobs. I run a generator, but have a small sub panel to hook up to a 30amp breaker for shore power (heat in the trailer over night). I run a ground wire from the subpanel to the main panel and utilize the earth ground from the temporary panel at the jobsite. I know I should drive a ground rod everytime I use the machine, but I just haven't bothered so far. I will be doing so in the future as I sure don't want a problem down the road. Hey at least I have an excuse to buy a new hammerdrill to drive the ground rods in. BTW I spoke with an electrician about this and he feels that 1-2 feet would be sufficient for temporary use. Residential code requires 8' but you would be hard pressed to remove that rod and you would never drive it with much success in the winter when the ground is frozen.

Tim
Granite State Spray Foam Co.

Rob Granger

Posted: Mar 26, 2008 08:05 PM

I have a shore cord that has four conductors. Two for hot, one neutral, one ground.. A sub panel always must have seperate neutral and ground bars within.

John Thrash

Posted: Mar 27, 2008 09:08 AM

Thanks for the advice.

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