Ground Wire to Workshop

[dnoonkeste]

My workshop has 3 wires from the main panel in the house that runs to the sub-panel in the workshop. Do I need to have a separate ground wire? When it was installed before 2007 a separate ground wire wasn't used. I read that a separate ground wasn't required then. Is that true?

 

[Jeff H Young]

No Idea what code was but You need 4 wires 2 hot 1 ground and 1 neutral that run back to main if you were building it now. Then the ground and neutral bond at main panel . I wouldnt know how important it is to not bond them at the sub. or why just what I seen and heard

 

[Sponsor]

 

[Afjes]

If the line was run for a particular device/appliance in the workshop that only required 3 wires such as two hots (240v) and a ground then this would be ok, or 120v, one hot, neutral and ground.

If the line was going to a sub panel in the workshop and the conductors/wires were located in metal conduit the entire way then the metal conduit in most cases would suffice as the ground to the sub panel.

In your case going to a sub panel and not contained in metal conduit the entire way (if this is true) then you do need a ground.

 

[Jeff H Young]

If the line was run for a particular device/appliance in the workshop that only required 3 wires such as two hots (240v) and a ground then this would be ok, or 120v, one hot, neutral and ground.

If the line was going to a sub panel in the workshop and the conductors/wires were located in metal conduit the entire way then the metal conduit in most cases would suffice as the ground to the sub panel.

In your case going to a sub panel and not contained in metal conduit the entire way (if this is true) then you do need a ground.

Alfes,
Wouldnt he need a ground at a sub panel he has? I get if its 120v he needs a neutral and only 3 wires , and 240 only he can skip the neutral. but in any case he needs a ground right? he says he has no ground that cant be ok right?

 

[wwhitney]

Per NEC 250.32(B)(1) Exception No 1, if you have an old, compliant at the time, feeder without EGC to an outbuilding, then you can continue to use it as long as no other metallic paths exist to the building (such as a metal water line, telephone line, cable line, etc).

In that case you treat this feeder without EGC as if it were a service: you connect the outbuilding's grounding electrode system to the feeder neutral, and you establish a new EGC system at the outbuilding with a bonding jumper to the feeder neutral.

As Afjes commented, if the feeder is contained in a continuous metal conduit, that is your EGC, and the above does not apply.

Cheers, Wayne

 

[Fitter30]

Add a ground rod to the sub panel for lighting protection. Still need a ground wire back to the main panel.

 

[Jeff H Young]

Add a ground rod to the sub panel for lighting protection. Still need a ground wire back to the main panel.

If the line was run for a particular device/appliance in the workshop that only required 3 wires such as two hots (240v) and a ground then this would be ok, or 120v, one hot, neutral and ground.

If the line was going to a sub panel in the workshop and the conductors/wires were located in metal conduit the entire way then the metal conduit in most cases would suffice as the ground to the sub panel.

In your case going to a sub panel and not contained in metal conduit the entire way (if this is true) then you do need a ground.

the part I dont understand Alfie s Ive read this a few times . So as dnoonkest has informed us the panel in his workshop has 3 wires going back to the main. NONE of which are grounds dosent make sence to me what would those 3 wires would be? dont say ground because we estabished there is no ground. 2 hots and a neutral (3 wires) is that legal or was that ever legal? it could be thats exactly what you and wayne are suggesting , i didnt know and just want it clarified

 

[Fitter30]

the part I dont understand Alfie s Ive read this a few times . So as dnoonkest has informed us the panel in his workshop has 3 wires going back to the main. NONE of which are grounds dosent make sence to me what would those 3 wires would be? dont say ground because we estabished there is no ground. 2 hots and a neutral (3 wires) is that legal or was that ever legal? it could be thats exactly what you and wayne are suggesting , i didnt know and just want it clarified

Everything that i read ground rod for lighting protection that can't be used as a panel ground.

How to Ground a Subpanel in a Detached Building - Circuits Gallery

To ground a subpanel in a detached building, pull 4 conductors and separate the grounded and grounding bus. This part is covered by National Electrical Code article 250.32, although it is one of the longest and most complicated portions in the whole grounding chapter, and it may be quite...

www.google.com

 

[wwhitney]

the part I dont understand Alfie s Ive read this a few times . So as dnoonkest has informed us the panel in his workshop has 3 wires going back to the main. NONE of which are grounds dosent make sence to me what would those 3 wires would be?

Implicitly, 2 hots and a neutral for a 120/240V system.

2 hots and a neutral (3 wires) is that legal or was that ever legal?

Yes, up through and including the 2005 NEC, the feeder to an outbuilding could be run "like a service" with no EGC, and the grounded circuit conductor (neutral) used as the fault clearing path, and a new EGC system established at the outbuilding, as long as there was no other metallic path to that building. In the 2008 NEC and subsequently, the practice was prohibited for new work, but existing feeders installed in this way make remain in use.

Cheers, Wayne

 

[Jeff H Young]

Implicitly, 2 hots and a neutral for a 120/240V system.

Yes, up through and including the 2005 NEC, the feeder to an outbuilding could be run "like a service" with no EGC, and the grounded circuit conductor (neutral) used as the fault clearing path, and a new EGC system established at the outbuilding, as long as there was no other metallic path to that building. In the 2008 NEC and subsequently, the practice was prohibited for new work, but existing feeders installed in this way make remain in use.

Cheers, Wayne

Thanks !