[ancientoaks]

We have a mobile home meter on a pole at our farm (w/ 200 amp service panel) (installed just for this purpose, there is no mobile home on it and never will be) and we plan on running the power from here to our equip shed to a main service panel... then run off this to our small barn.. distance from pole to she - 75 ft. distance from shed to barn - 40 ft
Shed needs : - 3 - fluer. Lites 3 outlets(GFI) capacity for lite welder

Barn needs - approx 8 lites approx 8 outlest well pump (220) hot water heater (40 gal)
QUESTION #1:
Size of cable (buried in ground) needed to the shed, then on to the barn. Same one? #4 alum?
QESTION #2 - any additional info needed is appreciated.. just want to know to be sure job is done right.. like to stay involved, am the grunt on the job!

Why are we told by some that alum cable is dangerous? It's not in the house/barn/shed but just a service cable underground, so it there still a danger factor here?

THANKS!!
(ps we live in a very rural, relaxed area, pole install, service panel, and meter already inspect and approved... nothing else is required. (soon, but things have not changed as yet!)

[nonadjustablemind]

I'm don't know the size req for such a job, the prob with alum wire I have heard is that underground and in panels it is easy to carrode (or however you spell that) and melt under heat condition and heavy water conditions


That is just what I have heard.

[tkrussell]

Aluminum cable for distribuiton feeders is widely used. The horror stories are from when AL wire was tried in homes years ago, and stopped and banned after a few years.


For underground, use #4/0 Aluminum URD cable (Underground Residential Distribution). Sometimes called "Trailer Cable" . Do not use three wire from the serivce to the next panel if the main switch is at the meter. Must use 4 wire, has two #4/0 for the hots , one #2/0 for the neutral, and a #4 for the equipment ground, whci must start at the main switch enclosure.

Use # 4/0 , not #4 for the 200 amp run, use a #1 or a #2- 4 WIre URD to the barn for a 100 amp service or less.

Dig a trench 30 " deep , lay a bed of 6" of sand, lay cable, lay another 6" of sand, backfill 12 in of natural material, leaving out large rocks, lay a cable warning tape, and back fill with natural material to grade.

Use 3 " PVC Sch 40 or DB conduit as a sleeve at paved roads or gravel roads with truck traffic. Offers added protection and allows for easy replacement if necessary. Code requirement due to soil conditions in many areas.

Never cheat on the trench. Having a live cable surface or get cut is no fun

There are miles of Al cable feeding homes, stores, etc, across the country. The issue with Al cable is the connections or terminations. Most of the utility uses Al wire. Copper was always, and sure is now, too costly to use on long runs.

I hear there is a Al alloy now made that does not need antioxidant compound, old fashioned here, will continue to use it.

An antioxidant compound must be applied to all Al bare wire connections, after being wirebrushed. Torque all connections according to manufacturer of the lug specifications. All electrical equipment is furnished with a label giving the torque specs for the lugs.

Once bare aluminum corrodes to aluminum oxide, the conducting properties change to a high resistance, and heat is created. The use of antioxidant, a gray grease like compound, works just fine, and AL cable will provide years of good service.

What most people domt realize is that a connection needs periodic maintenance, per all manufacturers instructions, esp under hard usage, checking the torque tightness of all connections. Doing this will certainly prevent any problems at all.

Use standard 2 or 3 in PVC Sch 40 conduit and the proper fittings to sleeve at the points the cable needs to rise into the meter and panel.

Will this barn house livestock? And are you aware of how to insure an Equio-potential Ground Plane to protect the livestock? Even if not necessary, be sure all grounding is done properly.