My hunting camp electric service

medinaex.2@zoominternet.n

I spoke to the Power company today. I need to schedule a meeting on site. They don't quote anything over the phone. I'll need to take a day off from work but It should be worth it..I really want it done right.

Will probably abandon the 100 amp pole service and start fresh. Whatever the co-op thinks would be best. I just hope it's not too big a check to write!!!

Hopefully I'll free up one day next week.

Thanks again for the help!

jrclen

If the wire is protected by a 200 amp over current protection device, it must be a minimum of 4/0 aluminum wire. It doesn't matter if your pulling 3 amps. See table 310.15 B 6. See also table 310.16. Use the 75C column.

You are correct, the load will determine the voltage drop and thus the conductor size for his 325 foot run. But it no case will the feeder be allowed to smaller than that required for his over current protection device. For a service feeder, it is common practice to use the service size to calculate voltage drop as loads can and do change in dwelling units. In the OP's case that would be 100 amps. A 4/0 aluminum wire would give him a 2.5 percent voltage drop on the feeder if his load was 100 amps.

Your feeder works just fine for you. But it is not in compliance with the National Electric Code, and you would have been required to replace the 2 ungrounded conductors (600 feet of wire) had the inspector been doing his job. Unless it is a lateral, installed and owned by the POCO as Petey mentioned.

It is never prudent, nor morally justifiable for an electrician to tell Do It Yourself people "what they can get away with." We must tell them what is correct and code compliant.

Randell Tarin

Unfortunately, it was the local POCO that told me to go with 3/0. I'm in the county with no inspector, so there was no one to call me on it; I trusted the power company.

jrclen

It was very common in my area also for the POCO to give advise slightly outside the code. They are not required to follow the NEC. Now we have permits and inspections.

At 300 feet, with the 150 amp load you mentioned, I calculate an 11 volt drop or 4.6 percent on the feeder. If you have little or no voltage drop in the branch circuits, you might still be under the 5% recommended maximum. The ampacity of your 3/0 aluminum is actually 155 amps, assuming it is common direct burial wire. Just some trivia information for you. I'm not suggesting it will burn down the neighborhood or jump out of the ground and hurt you.

But I don't want anyone else to make a similar install, thinking it's compliant and correct.

LawnGuyLandSparky

Here's the thing - if you're coming off your existing pole mounted service, what you do after the meter has nothing to do with the POCO. Your only option for an U/G service set by the POCO is to practically move it to the new cabin location, utilizing the last pole as the start of the U/G service. That puts the distance between new and old location in the POCO's court.

Generally, POCOs (especially coops I would imagine) do not want to run large guage wire for great distances. It flys in the face of everything a transmission & distribution utility stands for! It would be cheaper for them to run a distribution-voltage cable (much cheaper per foot) underground to a small padmount transformer.

micromind

The original post clearly stated a 100 amp service, that's what I based my recommendation on. If it's a 200 amp, I'd use two 350MCMs, a 250MCM for the neutral, and a 2/0 for the ground.

350's likely won't fit in a 200 amp breaker though, but there are ways to make this work.

Rob