Utilities secondary conductors to residence.

Status
Not open for further replies.
N

nizak

Senior Member
Question.

Does a secondary 600' run of 2/0 AL conductor seem undersize for a 200 amp 120/240 V residential service?

Calculated load to dwelling and detached building is right around 120 Amps.

Originally the job was designed for primary power to travel about 500' then have a pad mount xfmr and from there to the dwelling.

Crew shows up and trenches in the secondary all the way from a pole mounted xmfr at the road.

Any thoughts?
 
at a 120 amp load, voltage drop would be about 23 volts on a 240v load.
 
nizak said:
Question.

Does a secondary 600' run of 2/0 AL conductor seem undersize for a 200 amp 120/240 V residential service?

Calculated load to dwelling and detached building is right around 120 Amps.

Originally the job was designed for primary power to travel about 500' then have a pad mount xfmr and from there to the dwelling.

Crew shows up and trenches in the secondary all the way from a pole mounted xmfr at the road.

Any thoughts?
Click to expand...
Voltage drop might be somewhat of a problem at that length, especially when AC compressor starts.

Otherwise for a dwelling you can take advantage of 310.15.(B)(7), but for 200 amps single overcurrent device that still leaves you with 4/0 aluminum as minimum. Your 2/0 would comply if you had a 175 amp main and load calc was no more then 145 amps.
 
ptonsparky said:
CYA. Make sure customer is aware of who sized and installed the lateral.
Click to expand...

I agree.

I would voice my concerns to the customer and give them the option of allowing us to install our Fluke logger on their service for a short period of time to verify voltages stay within acceptable tolerances.
 
Status
Not open for further replies.
Top