I am building a garage for my boat and truck. My building is 200ft away from the meter on my house. I was told to run #2 aluminum wire but when I went to get the wire at lowes they told me 200ft was too much length for a 100amp service. They said I could only get around 50amp of power out of it on this length. Is this right? Is 50amp enough to run much stuff?
first of all, what is the size of the main service at your house, and , what type, size of load are you anticipating in the garage ? if you have equipment, ie air compressor, welder, freezer, etc it makes a difference.....basically- the bigger the load, the bigger the wire needed..... a list of nameplate ratings of the equipment is necessary to do a proper load calculation....
dont forget...the guy at lowes......
im going to be NICE and not say anything....
He is right and wrong! At 200' underground I do not think you would see enough voltage drop to be a concern although 100 amps on #2 is a strain I would not go over 90 amps with #2.
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by ol man river »</td></tr><tr><td class="quote">first of all, what is the size of the main service at your house, and , what type, size of load are you anticipating in the garage ? if you have equipment, ie air compressor, welder, freezer, etc it makes a difference.....basically- the bigger the load, the bigger the wire needed..... a list of nameplate ratings of the equipment is necessary to do a proper load calculation....
dont forget...the guy at lowes......
im going to be NICE and not say anything....
Sam, How long have you been a Electrian now, I guessing 30 years by now.
What Sam said is what I'd go with.
#2 or 2/0 aluminum?
I would have a problem eith the credibility with the help at lowes too!
for residential applications....
CM = 2KIL divided by VD
this is the formula for figuring single phase voltage drop/ wire sizing......
in your case, unless you are going to be doing some serious welding, machine work, or the like, a 100 amp service should be more than adequate for your needs....the cheapest option is direct burial cable....2-2-4-6 trailer cable is what to use, but to be sure , id use 1/0-1/0-2-4 trailer cable.......the BEST installation would be to use 1 1/4 pvc conduit and pull in 3 # 2 copper thhn, with a #4 ground...but it will be a bit pricey compared to the trailer cable
and yes, Mike, ive been in the trade for right at 30 years now
Agreed, has to be 2/0... And it'd run that all day long, I've had 75' pulls inside a house w 2/0 on 150a. Being direct burial/ triplex won't affect what the service will hold and really that isn't that long of a distance in all actuality. Besides even w a 100a sub panel you will likely rarely use that much draw at once unless you have hvac, a compressor, and a welder going.
Greg
06 Stratos 201 ProXL, Yamaha 225
12 Ram 1500 QC Hemi, Dropped 5"+
85 Tidecraft turned mega pond boat
Just for clarification #2 and 2/0 are a huge different!
Thanks for the help guys. My meter is a 200amp. It may be 2/0 instead of #2. I have already buried a 3" conduit from my meter to the building. I will be running a air compressor, hand tools, lights, small heater in the winter, and possibly a small welder. The welder I think is 220 or atleast it has the big plug in. I want to do it the cheapest way but I do want enough power there. Can I run the aluminum 2/0 (I think the numbers are 2 2 2) wire the 200' and use a 100 amp breaker and run all the things listed?
Thanks again I need all the help I can get.
Are you feeding from your house panel or from the meter also you want to check what the largest wire is that the lugs on the 100amp breaker will accept. I would use alum. in your situation copper is better but a big cost difference.
voltage drop starts at 150' . after that you continue to upsize the conductor to compensate. with that being said, i agree you will probably never pull 100 amps . tell us what you are running and plan on running in the future.
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by get5fast »</td></tr><tr><td class="quote">Thanks for the help guys. My meter is a 200amp. It may be 2/0 instead of #2. I have already buried a 3" conduit from my meter to the building. I will be running a air compressor, hand tools, lights, small heater in the winter, and possibly a small welder. The welder I think is 220 or atleast it has the big plug in. I want to do it the cheapest way but I do want enough power there. Can I run the aluminum 2/0 (I think the numbers are 2 2 2) wire the 200' and use a 100 amp breaker and run all the things listed?
Thanks again I need all the help I can get.</td></tr></table>
are you putting in a new service to the building ( shop/garage) or a sub feed from the main service ? this makes a HUGE difference.....
---------------------------------------------
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by toddgot5fish »</td></tr><tr><td class="quote">voltage drop starts at 150' . </td></tr></table>
Really ?
Do Tell......
I guess it is a sub feed from the meter box on my house to the shop where there will be a breaker box.
So correctly me if I am wrong but I will not be able to get 100amps to the shop with the 2/0 aluminum wire coming offf my meter 200ft away. How many amps will I be able to carry the 200ft with the aluminum wire and will it run the above mentioned power sources.
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by get5fast »</td></tr><tr><td class="quote">I guess it is a sub feed from the meter box on my house to the shop where there will be a breaker box.</td></tr></table>
you will not be able to 'tap ' off of the meter box to run a sub feed to the shop, the wire has to be protected by a breaker or fuses..it will have to be run from your main panel inside the house, unless its a trailer with a trailer pole meter can / main panel......
direct burial trailer cable ( it comes with 2 hots, a neutral and a ground wire, pre grouped together ) will be your best bet i think.....with the loads you described, it may be best to use 2/0-2/0-1/0-4 trailer cable....it could be overkill with your situation, but upsizing the wire never hurts when in doubt.....the only issue is trying to land larger conductors on breakers meant to connect smaller ones......
I have a seperate side not being used on the meter box for breakers. I have already reduced the conduit size from 3" to 2" to go in to the meter panel. I am just trying to figure out the right wire to buy.
if possible , i would look at a size above the 2-2-2-4 aluminum rated for direct burial . i dont think you can physically get a 2/0 in the lugs of a 100 amp breaker ,but may be able to on a 125 amp breaker. you may come out ahead to price your conductors at a local electrical supply house . . .the big stores have a limited supply of wire sizes
ok, hang on I might bore you, but trust me I know
I assume you are running single phase 120/240v @ 60HZ with a buried cable or in PVC conduit buried. YOu would need to run two phase conductors, one nutral conductor and a properly sized ground wire. You must seperate the ground and the nuetral bars in your sub panel at the garage, Otherwise you run the potential of a floating nuetral situation (must be done on a subpanel). YOu will also need to drive an additional ground rod for the subpanel ground; this is in addition to the ground wire from your main to your sub. 100 amp subpanel should be fine. You can run a #2 copper, which is rated for 95 amps, little undersized by code but sometimes the proper #1 copper is hard to find. Don't have my books with me but i found a voltage drop calculator on the internet, you should not install a load of more than 80 amps on a 100 amp subpanel, by code. The #2 will have a voltage drop of 2% at 200 feet with a 80 amp load (my memory tells me the calculator is close). IF you run aluminum you will need to install #1/0 which will result in a 2.1% VD.
I need more details to be more specific, but this is close. Ask any questions you like, I will glad to answer, but I have found in most cases the novice electrician is better off to hire a licensed electrician to complete the install, as there are many details to be worked out to have a properly operating electircal system. Oh yes, the gentlemen above is correct, the buried set up comes with all wire he told you and presizes your ground wire by code.
Reply With Quote
Lowes.
