No EGC but there are GECs

[Elect117]

The contractor is claiming the transformer was already there and is not part of his install. There is no EGC for the transformer. When I was doing the inspection, I noticed the transformer only tied to the water line but not to the building steel less than 1ft from it. So I asked him to extend the electrode system to the building steel.

When he called for a final, I noticed he tied in an extra wire, I am going to call it a GEC, to the 480V panel that feeds the transformer. When I asked to see the panel, he removed the cover to show that there is no EGC present in the 480V 3PH panel (very old panel).

His install is a new 120/208V panel off the dry type for some EV chargers.

I can not wrap my head around why he would run a GEC to the 480V panel. He didn't list a reason other than it is metal and not grounded and in proximity to the electrical equipment.

All the conduit is EMT.

I can post photos if requested.

My gut is telling me to tell him to remove the GEC he decided on running to the 480V panel and pull an EGC from the main, to the 480V (400A) and then to the transformer (125A). I have no idea what the main looks like and it might not have grounding lights or a high resistance ground.

Any advice is appreciated.

 

[Dennis Alwon]

If the conduit is emt then there is a ground. Emt is suitable for use as a equipment grounding conductor.

358.60 Grounding.
EMT shall be permitted as an equipment grounding conductor.

 

[infinity]

As Dennis stated the EMT is the EGC on the primary and the SSBJ on the secondary which is permitted by the NEC. The GEC to Panel 1 is not required.

 

[Elect117]

If the conduit is emt then there is a ground. Emt is suitable for use as a equipment grounding conductor.

I stand corrected in asking him to run a EGC from the 480V panel to the XFMR. I am just used to see one run so that it can all land on the same grounding bar (450.10).

"450.10 Grounding.
(A) Dry-Type Transformer Enclosures.
Where separate equipment grounding conductors and supply-side bonding jumpers are installed, a terminal bar for all grounding and bonding conductor connections shall be secured inside the transformer enclosure. The terminal bar shall be bonded to the enclosure in accordance with 250.12 and shall not be installed on or over any vented portion of the enclosure.
Exception: Where a dry-type transformer is equipped with wire-type connections (leads), the grounding and bonding connections shall be permitted to be connected together using any of the methods in 250.8 and shall be bonded to the enclosure if of metal.
ENHANCED CONTENT
An enclosure typically is not evaluated as a grounding and bonding device. The required busbar for EGCs and bonding jumpers prohibits the practice of using the transformer metal enclosure as a connection point for these conductors.
"

The enhanced content from the handbook threw me off.

I couldn't tell if the 480V feeder circuit (feed from underground) is functioning as a EGC. If that is the case, then I will just instruct him to remove the additionally placed GEC.

As Dennis stated the EMT is the EGC on the primary and the SSBJ on the secondary which is permitted by the NEC. The GEC to Panel 1 is not required.

Not required but okay to leave as it? Or ask him to remove it?

 

[Dennis Alwon]

Not required but okay to leave as it? Or ask him to remove it?

Not my area of expertise but I don't see what it can hurt if it is left alone.

 

[infinity]

Not required but okay to leave as it? Or ask him to remove it?

I see no reason to require that it be removed. Any metal raceway connected to both the panel and the steel would be doing the same thing.

 

[Elect117]

Thanks all for the insight.

I will let him know I looked into it and it is okay as is.

I had a different correction for him on metal boxes he has spliced in and didn't bond the EGC to the case (even though everything is emt). Those boxes are not pictured. It is where he ties in the car charger's cord to the branch circuit conductors with listed pressure connectors. Even still I am arguing with myself on it.

I know it is 250.148 + 250.148(C), 314.4 , 250.109 but I see the conductor as the emt and the wire.

Since the wire was run and spliced in the box, he should also land a connection to the box?

 

[Dennis Alwon]

Thanks all for the insight.

I will let him know I looked into it and it is okay as is.

I had a different correction for him on metal boxes he has spliced in and didn't bond the EGC to the case (even though everything is emt). Those boxes are not pictured. It is where he ties in the car charger's cord to the branch circuit conductors with listed pressure connectors. Even still I am arguing with myself on it.

I know it is 250.148 + 250.148(C), 314.4 , 250.109 but I see the conductor as the emt and the wire.

Since the wire was run and spliced in the box, he should also land a connection to the box?

I agree with you. 250.148(C) clearly states that the equipment grounding conductor must be connected to the box. Since the equipment grounding conductor is in the box then a jumper is needed to the box regardless of whether the wiring method is emt or not. Seems redundant but that is how I read it.