Service for house with attached apartment

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Legrand

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New Mexico
So, I got a call on Sat. The tree trimmers caught the tri-plex, ripped the transformer half off the pole, and destroyed two service risers on a home with an attached apartment. Now I have to install one new riser go to a junction box, split to two meter cans with disconnects and re-feed the home and apartment. I'm not sure exactly how to do this, as I have never done this before. If someone could critique my plan I would greatly appreciate it. I have not done a load calc on the home or apartment, but I plan to install 100a meters and disco's to each. 120/240

2" IMC Service riser
2/0 service conductors 200a
LB into side of 6"w x 24"L x 6" deep gutter
2 runs of 1" EMT to the 125a rated Meter/Disco's w/#4 wire 100a
3 #4's w/#8 ground wire from load side of disco to feed each of the house and apartment panels #8 ground wire does not seem right, I'm not sure where to size that I used 250.122
2 8' ground rods #4GEC
#4 running to water pipe
Intersystem bonding terminal somewhere in there

I'm not sure how to go about my main bonding jumper, I suppose the GEC needs to run into both disco's?
Do my service conductors need to be rated at 200a?
I'm not sure if the emt is will be and effective fault path from the riser back to the disco if they're ringed knockouts on the meter/disco maybe just a grounding locknut inside the meter?
 
why are we re-inventing the wheel ? Why not just go back with the two risers ?
 
Locally, If you fed the wireway with 2/0, a load calculation would be required. Most folks just use 3/0 in those instances. I would install a grounding bar in my wireway which would serve to bond the wireway and a connection point for my grounding electrode conductors. If possible, PVC into my service disconnects to avoid bonding bushings/locknuts. One would be required on your riser.
Two gang meter sockets are a more common approach here.
 
Ok so I use 3/0, avoid load calc, place ground bar in gutter, run #4 from rods and water pipe into gutter, then 2 runs of pvc and #4 to a 2meter panel with 2 100a brkrs. My GEC needs to bond to the neutral at the first means of disconnect I believe which would mean after the meters on the brkr side, two bonding jumpers from the gutter? I'm not sure how these two gang meter sockets are set up, would it be one run of 3/0 avoiding the gutter, or two raceways with #4? I like your way a whole lot better than mine.
 
Legrand said:
Ok so I use 3/0, avoid load calc, place ground bar in gutter, run #4 from rods and water pipe into gutter, then 2 runs of pvc and #4 to a 2meter panel with 2 100a brkrs. My GEC needs to bond to the neutral at the first means of disconnect I believe which would mean after the meters on the brkr side, .
Click to expand...
GEC can connect any place between the POA and 1st discoonnect.
Easier just to run all your GEC to the gutter normally...(rarther than two service disconnects/meters
Legrand said:
two bonding jumpers from the gutter?.
Click to expand...
Bonding jumper to metalic service conduit is all I can think of (if you use PVC to the meter/panel).. Ground bar mounted to the wireway will bondf it.

Legrand said:
I'm not sure how these two gang meter sockets are set up, would it be one run of 3/0 avoiding the gutter, or two raceways with #4? I like your way a whole lot better than mine.
Click to expand...

If they are available and acceptable to POCO, yes. Depending on the brand, they normally have a center section to connect your riser and GECs. Sockets with a built in gutter :grin:
 
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