Underground wire size question

[zoedog2012]

A panel of some sort. I will be there tomorrow so can look closer at meter, open panel and get more info. Thanks for the help.

 

[RNeumann]

It should have at least a breaker. Either it has a panel or I'd set a panel there. From the panel I'd run 2 conduits- one for the shop and one for the house. The wire size and conduit size depends on copper or aluminum. Decide that and the calcs are pretty straight forward. With the cost of copper most would do aluminum but it's up to you.

 

[TemporaryKubotaOwnerMark]

If you just run the bare minimum that you think you want now, you will be cursing yourself some day. At least if you put in the conduit (as suggested), you can later upgrade without having to dig again.

 

[NewfieDan]

Since this subject came up, I need help also. We are building new house and shop and want to run single phase 300 amp service from meter 425 feet underground. Want 200 for the house and 100 for shop. What size wire do we need? Thanks

I would probably look at a 400A sevice. The extra cost for what you are planning would be minimal. This would also allow you plenty of room for future. Also find the largest panel you can. One person mentioned a 30cct panel. You will find that this does not have enough room for the circuits you will want. Things like fridges, freezers, microwaves, and most large appliances require their own dedicated circuit. There are also a specific number of outlets allowed on any circuit. The larger the house the more circuits will be used just for outlets.

The heat and AC loads also make a difference. What kind of heat will you have? Base board heaters will also use up spaces in the panel, compared to something like a heat pump that only uses a couple of spaces. There are rules in NEC and CEC that will help calculate this.

 

[buickanddeere]

That would be a 200Amp from the meter to the house. 100 amp from house to shop/shed. Not sure of the local codes but that would be at least 250mcm copper for the 425 ft. When doing the complete job this would be the time for a main service with a generator transfer switch.TWB212DR Panel/Link - Reliance Controls Corporation

 

[2ndhalf]

To further drive the point home- Home Depot has 1 1/2" pvc conduit listed for $0.62/ft or about $112 for the run-they don't list 1 1/4" on the website.
To have 4 8 ga wires (1000' of wire) is $274. 4 wires gets you 2+ circuits and or 240v.
Total $384 plus conduit ends.

The direct bury 10/2 romex is $175 The non outdoor rated (that's all HD had listed) 8/2 was $375 plus conduit ends. Direct bury is more!

So for about the same price as direct bury romex that only gets you one or two circuits and no 240v option you can have multiple circuits (double the power/amps of the romex) and 240v. Plus the conduit is big enough to upgrade the wires for anything you would want to do in the future. You have to dig the trench anyway- might as well use the conduit.

I would also put it in the gray conduit from lowes or HD and use the non-underground wire. I found this cost differential to be true when I made my run to my garage from the house. It is easy to work with and the wire is in conduit I didn't bury mine very deep either. For some reason that underground wire is out of site expensive; also a pain to work with.

 

[2ndhalf]

The meter is very near the transformer, and all the service is underground so yes the 425' is after the meter. To make matters worse our 8 acres is in a HOA. The developer had all the infrastructure done upfront,city water, phone. No NG,only buried propane tanks are allowed.

If HOA here means what I think it do.... your a licensed electrical contractor right? I would not attempt this job on your own being in an HOA or your asking for trouble IMO.

 

[RNeumann]

I would probably look at a 400A sevice. The extra cost for what you are planning would be minimal. This would also allow you plenty of room for future. Also find the largest panel you can. One person mentioned a 30cct panel. You will find that this does not have enough room for the circuits you will want. Things like fridges, freezers, microwaves, and most large appliances require their own dedicated circuit. There are also a specific number of outlets allowed on any circuit. The larger the house the more circuits will be used just for outlets.

The heat and AC loads also make a difference. What kind of heat will you have? Base board heaters will also use up spaces in the panel, compared to something like a heat pump that only uses a couple of spaces. There are rules in NEC and CEC that will help calculate this.

The 30 or 42 count panel is at the road. It comes with the 200a breaker and is a 400a panel. The Siemens I referenced has all copper bus bars and a full selection of breakers available that are competitive priced. Plus the panel is about the half the price of other brands (with aluminum buses)- even from the wholesale.

So at the road you would only need a few spaces of the 30 or 42- the shop for sure and maybe power near the road or a gate.

Then at the house and shop you would technically have sub panels. You are correct- The one for the house should be at least a 42 space panel. Especially now with almost every circuit requiring GFCI, Arc Fault and or Combination breakers.

 

[buickanddeere]

Since this subject came up, I need help also. We are building new house and shop and want to run single phase 300 amp service from meter 425 feet underground. Want 200 for the house and 100 for shop. What size wire do we need? Thanks

What is using so much power to require that size of electrical service ?

 

[topbuilder]

200 amps for a house is pretty standard. 100 amps for a shop is pretty minimum. I have 200 amps to each.