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grubin
Jan 18, 2013, 06:14 PM
I am installing a 400 amp service on my property in Portland, Or. I will be using a double 200 amp meter base with 200 amp breaker disconnects. Just to clarify, this is a panel that has two separate 200 amp meter bases. I will be running one of the 200 amp legs to a 200 amp service panel in the house, within 10' of the meter bases. From the 200 amp service panel I will be supplying a 100 amp sub-panel in the utility room (about 35' run away).
1. What size wires and conduit should I use from the meter bases to the weather head?
2. What size wire should I use from the 200 amp meter/disconnect to the 200 amp service panel?
3. What size wire should I use from the 200 amp service panel to the 100 amp sub-panel? I will have a 100 amp breaker in the 200 amp panel for the supply.
4. As an alternative to the above scenario, I may instal the 200 amp service panel in the utility room, eliminating the need for the sub-panel (which is actually my existing main panel). In this scenario, what size wire should I use going from the meter/disconnect to the 200 amp service panel 35' away.
5. Also, most of the existing wiring in my house does not have ground wires. I would like to replace all the wiring, but would prefer to do it one room at a time, as we remodel, over the next year. Will the inspector expect to see everything in the panels grounded when they inspect my installation of the meter bases and service panel?
Thanks

tkrussell
Jan 19, 2013, 04:11 AM
Assuming each meter has its own riser conduit, 3 - #4/0 aluminum XHHW, or if using SE cable, 4/0 Al 3 Wire SEU cable for each.

To the 200 amp panel, assuming SE cable, use #4/0 4 wire SER cable.

As long as no renovations are being done in the home, the inspector should not require any changes to the branch circuit wiring.


I have to ask, why two separate meters? Most utilities charge a monthly service charge for each meter.

They do make a 400 Amp (AKA 320 Amp) meter socket with two 200 amp breakers built in. Can save one monthly service charge.

grubin
Jan 19, 2013, 12:18 PM
Assuming each meter has its own riser conduit, 3 - #4/0 aluminum XHHW, or if using SE cable, 4/0 Al 3 Wire SEU cable for each.

To the 200 amp panel, assuming SE cable, use #4/0 4 wire SER cable.

As long as no renovations are being done in the home, the inspector should not require any changes to the branch circuit wiring.


I have to ask, why two separate meters? Most utilities charge a monthly service charge for each meter.

They do make a 400 Amp (AKA 320 Amp) meter socket with two 200 amp breakers built in. Can save one monthly service charge.

I may be using one of the 200 amp services for a future business on my property. On the other hand, if it is going to cost me a lot more money to have a separate meter, maybe I should just go with the 400 amp socket. I remember when pricing them, they were spendy. I already have a double 200 amp meter base that I picked up cheap. Oh well. I guess I will be calling my utility company to see what the cost difference of the two services is.
If I do go with the 400 amp socket, what size conduit and wire should I use for the mast?
Thanks a lot for the help!

tkrussell
Jan 21, 2013, 05:59 AM
One riser for a 400 amp meter would Need min of 3- #600 MCM Aluminum XHHW conductors in one 3 inch PVC Sch 40 conduit, or there can be two 2 inch PVC conduit risers each with a set of 3- #300 MCM Al XHHW conductors.

Since you already have two meter sockets, with plans for two separate metered services, you can stay with your plan.