Feeder for sub panel

[caskscob]

I am installing a sub panel in my newly built detached metal structure workshop. I have found conflicting information on the grounding for this. Previously I found multiple sources that indicated that you should run 3 conductors (L,L,N) from the main panel and then separate the ground and neutral bars at the sub panel and install 2 grounding rods at the sub panel minimum 6' apart. That is what I did. Now I am finding information that is saying I need to run a ground also from the main panel. Which is accurate? I ran 210' of cable in a trench from house to workshop already and I hope I don't have to dig that up to add a ground wire.

Thanks in advance.

 

[infinity]

You need an EGC run with the feeder sorry but there is no exception for new construction.

Welcome to the forum.

 

[don_resqcapt19]

With that much work required to install the equipment grounding conductor, you might consider a 240 to 120/240 transformer at the work shop. The existing neutral would be used as the equipment grounding conductor for the transformer primary. You would install a system bonding jumper on the secondary of the transformer and connect the workshop grounding electrodes to the neutral.

 

[LarryFine]

Previously I found multiple sources that indicated that you should run 3 conductors (L,L,N) from the main panel and then separate the ground and neutral bars at the sub panel and install 2 grounding rods at the sub panel minimum 6' apart.

No, that is deadly dangerous!

 

[Dennis Alwon]

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