Dual Meter Service Drop

[Mr. Sparkles]

Hello,
I am trying to upgrade a 100/100 drop to a 200/100. There is a gutter above the meters right now but I will put in a new one for PGE and tap off that for the new services. My question is, what is service wire for this size drop (technically 300 amps) PGE won't tell me what they want because it is on my side of the weatherhead they say. Which is weird because the gutter for the service taps will be locked out by PGE. I can't do a dual meter pack because distribution for the new 200 amp is right there already and they want a 20/40 in that space. Curious what the solution is. Any help would be appreciated.
Thanks

 

[tortuga]

If you take the service size as the load calc in those situations we'd have 90C or better utility rated connections at both ends so 300 KCmil or 350 AL kCmil for the 300Amp riser.
Or the size the service at the calculated load under art 230.

 

[Mr. Sparkles]

Thanks Tortuga. So if I derate 83% I still have to be using 250 CU for the riser wire. It's crazy no one has come across this. I have asked other electricians I know, the inspector for the city where I am doing the work and PGE. PGE rep assigned to this job told me that I could just use 2/0 CU even though 300 amps could in theory flow through the conductors.
Another PGE employee told me I needed 2 risers because it is 2 services and finally a third told me since it is a single residence that only a single riser would be fed from the pole but wouldn't say what size wire they would recommend. It's nutty how strict PGE is about certain rules (gas meter proximity to upgraded service) but couldn't pay them to care less about other things.
I am sure someone out there has done this before, if so any help would be appreciated.

 

[electrofelon]

Thanks Tortuga. So if I derate 83% I still have to be using 250 CU for the riser wire. It's crazy no one has come across this. I have asked other electricians I know, the inspector for the city where I am doing the work and PGE. PGE rep assigned to this job told me that I could just use 2/0 CU even though 300 amps could in theory flow through the conductors.
Another PGE employee told me I needed 2 risers because it is 2 services and finally a third told me since it is a single residence that only a single riser would be fed from the pole but wouldn't say what size wire they would recommend. It's nutty how strict PGE is about certain rules (gas meter proximity to upgraded service) but couldn't pay them to care less about other things.
I am sure someone out there has done this before, if so any help would be appreciated.

As you can see, many people don't know what they are talking about. Where one set of conductors feeds multiple service disconnects (per 230.40 exception #2 usually) those conductors can be sized to the load instead of the sum of the OCPD's (230.90(A) exception #3).

You can have a riser for each meter or a common riser, and in both cases it is one service.

You can only use the 83% rule in conductors serving an individual dwelling unit (so not a common riser).

 

[Hv&Lv]

. PGE rep assigned to this job told me that I could just use 2/0 CU even though 300 amps could in theory flow through the conductors.
Another PGE employee told me I needed 2 risers because it is 2 services and finally a third told me since it is a single residence that only a single riser would be fed from the pole but wouldn't say what size wire they would recommend..

The PGE employees overstepped their bounds. Utility personnel work under a different code than the NEC.
Very few are actually ECs.
I am one of three in our company.
None of the linemen are..
Thats the way it is at most utilities.
electrofelon nailed it with his first sentence above, and he’s right..

 

[Eddie702]

The riser wires only have to be sized for the calculated load. But no 83% derate.

I did a 3 family changed 3 60 amp panels to 3 100 amp panels and used a 200 amp riser. No load added.

 

[tortuga]

As you can see, many people don't know what they are talking about. Where one set of conductors feeds multiple service disconnects (per 230.40 exception #2 usually) those conductors can be sized to the load instead of the sum of the OCPD's (230.90(A) exception #3).

You can have a riser for each meter or a common riser, and in both cases it is one service.

You can only use the 83% rule in conductors serving an individual dwelling unit (so not a common riser).

All good points, I have a pretty good give and take relationship with our local AHJ, and this is one issue I give in to him on. On these service changes with multi family units he strongly prefers the riser to match the OCPD's.
If its its new construction its all underground (overhead is not allowed here anymore) and there are load calcs.