A troubling change in policy about pass/fail for feeders

[wbreslin951]

I recently had a temp power inspection, and the inspector informed me that effective on my next installation, the way I had installed it will fail inspection. I've since sent him an email after our conversation to get more details about where this change is coming from, but in my opinion it's a step in the wrong direction. The installation was performed as follows:

Underground feeders (4/0 - 4/0 - 2/0 - 6) were installed between a service rated 200A meter pedestal and a 200A Feed Through Exterior load center. The structure had a ufer ground and a building steel ground connected on a continuous conductor, with no neutral bond at the feed through panel. The neutral bond exists at the meter pedestal, which also has a ground rod.

The meter pedestal also has 4 breaker spaces (in addition to the 200A breaker and terminals), one of which will be feeding a well house, and the other, a barn subpanel. Both of which also have equipment grounds, with the barn having two new ground rods.

The change I was instructed to follow is this: remove the equipment ground from between the pedestal and building disconnect, the pedestal and barn disconnect, and install a bonding jumper at the building disconnect and barn disconnect.

It is my opinion, after looking through the definitions of feeder and service equipment in article 100, and then looking at 250.32(B)(1), that the installation as instructed would be a violation.

I'm still waiting for a reply that provides any local amendments that may contradict this interpretation.


All of this goes without saying that I believe this creates some major safety issues, especially in the event of a lost neutral. In my opinion it goes against the intent of a ton of code changes over the past couple decades, and everything I know about safe grounding and bonding practices.

I'm interested to hear any opinions on this subject, or some enlightenment on details I may be missing.

 

[LarryFine]

So, you're effectively being told to use 3-wire feeders.

For the pedestal-to-house-panel run, maybe okay, costs slightly less.

For the barn sub-panel, it would be clearly non-compliant.

 

[wbreslin951]

So, you're effectively being told to use 3-wire feeders.

For the pedestal-to-house-panel run, maybe okay, costs slightly less.

For the barn sub-panel, it would be clearly non-compliant.

There is no difference between the barn sub panel feed and the house subpanel feed, except feeder size and overcurrent protection. If it's clearly non compliant for the barn, it's clearly non compliant for the house, because they are both fed from the same "panel" which is the service rated meter pedestal.

250.32 specifically requires an equipment ground when feeding anything from a service rated pedestal as I understand it.

The only time an egc wouldn't be required is if the meter pedestal had no switch/breaker/means of disconnect and wasn't grounded. Tell me if you've ever seen one of those. I haven't in the last 15 years

 

[ptonsparky]

So he gave you no code references to support his preference?

 

[electrofelon]

Sounds like this guy is stuck in the 90s. We used to be allowed to run three wire feeders to remote structures in rebond at the remote structure, but that's been away for a long time. And even then, you didn't have to use the three wire feeder you could use 4 wire.

 

[LarryFine]

There is no difference between the barn sub panel feed and the house subpanel feed, except feeder size and overcurrent protection. If it's clearly non compliant for the barn, it's clearly non compliant for the house, because they are both fed from the same "panel" which is the service rated meter pedestal.

I missed that the barn feeder was also fed from the pedestal; I thought it came from the house panel. I was picturing the inspector calling the conductors leaving the pedestal as service conductors.

Yes, with multiple breakers supplying conductors leaving the pedestal, those are all clearly feeders and should include EGCs and should not have neutral-EGC bonding done in what are sub-panels.

 

[LarryFine]

Sounds like this guy is stuck in the 90s. We used to be allowed to run three wire feeders to remote structures in rebond at the remote structure, but that's been away for a long time. And even then, you didn't have to use the three wire feeder you could use 4 wire.

Agreed. I don't recall having a separate EGC ever being prohibited.

This sounds like a ruling based on "What I would have done."

Particularly funny because it is a non-compliant design choice.

 

[Dennis Alwon]

The first disconnect- the meter pedestal which has a 200 amp breaker is the main disconnect and has a neutral-to-ground bond. Nothing else does.... I wonder if he is thinking that the pedestal 200 amp breaker is an emergency disconnect therefore, you only need 3 wires to the second panel. I believe if that is it then he is all twisted on that section in the 2020 & 2023 NEC codes.

For that to apply the meter pedestal would have to say emergency disconnect and be labeled not service equipment. This is not the case so I think he is mis applying that section

 

[roger]

Show the inspector these illustrations.

 

[Bill Annett]

When I was doing Electrical Inspections for the City, I kept a paper copy ( I also had an electronic copy stored on my desk conputer ) of a lot of Mike Holts Illustrations. They came in very handy for me. I would sometimes do a pre inspection and give the homeowner or an Electrical contractor a copy of the illustration which would give them the information needed to do a code compliant installation. I am very thankful for Mr Holt and all of the other members of this forum.