1979 subpanels not 4 wire

[Stevenfyeager]

a fourplex building, two apartments upstairs, two offices downstairs, the meter base has four 200 amp breakers. From there are 3 wires to each of 4 inside panels, with neutral and ground connected together in each panel. In my remodeling, should I address these not being 4 wire, with isolated neutral ? The two offices on the ground floor are less than 10' of wire and wouldn't have required outside disconnects, correct ?

 

[ptonsparky]

We would have been required to have all the disconnects located in the same area. Outside.

Now would be a good time to address the 4 wire issue.

 

[texie]

a fourplex building, two apartments upstairs, two offices downstairs, the meter base has four 200 amp breakers. From there are 3 wires to each of 4 inside panels, with neutral and ground connected together in each panel. In my remodeling, should I address these not being 4 wire, with isolated neutral ? The two offices on the ground floor are less than 10' of wire and wouldn't have required outside disconnects, correct ?

I'm confused. You say the meter center has four 200 amp breakers. Then in your last sentence you are asking if you need outside disconnects that you already have at the meter center.
The 3 wire feeders were never compliant unless the raceway is a qualified EGC and the neutral is not bonded at the subpanel.

 

[tom baker]

Does the feed to the feeder panels qualify as an EGC per 250.118 (IE RMC, EMT...) Then just need to remove the bonding jumper in each panel.

 

[McLintock]

I way I understand, your first disconnect of a service needs to be bonded. So if the panel inside is the first one I would leave it alone. If at the meter base I would suggest to the owner what is the right thing to do per code. Do you have to bring it up to code?

You do not want your ground bonded at two,three, four points but one. So where is it first bonded?


“ shoot low boys their riding shetland ponies”

 

[A/A Fuel GTX]

I'm confused. You say the meter center has four 200 amp breakers. Then in your last sentence you are asking if you need outside disconnects that you already have at the meter center.
The 3 wire feeders were never compliant unless the raceway is a qualified EGC and the neutral is not bonded at the subpanel.

Three wire feeders were compliant at one time up to about 2002/2005 as long as there was no parallel path regarding the grounded conductor.

 

[texie]

Three wire feeders were compliant at one time up to about 2002/2005 as long as there was no parallel path regarding the grounded conductor.

That is true for an outside feeder. I don't think the OP has an outside Feeder as I understand it.

 

[Stevenfyeager]

The outside 4 meter base has 4 200 amp breakers. Those breakers feed 4 inside panels with 3 wire, and they are in metal conduit, so you are right, that conduit could be the EGC. But in each panel, the neutral bars are connected with a bonding strap to the enclosure. That seems wrong to me. Thank you

 

[ptonsparky]

The outside 4 meter base has 4 200 amp breakers. Those breakers feed 4 inside panels with 3 wire, and they are in metal conduit, so you are right, that conduit could be the EGC. But in each panel, the neutral bars are connected with a bonding strap to the enclosure. That seems wrong to me. Thank you

Remove the strap. Put in an equipment grounding bar bonded to the enclosure. Make sure your locknuts are nice and tight. Move all EGs to it. Use your imagination on how to deal with 3 wire ranges and dryers. They may need new wire, cords & devices.