The Forestry Forum is sponsored in part by:

iDRY Vacuum Kilns


Forestry Forum
Sponsored by:


TimberKing Sawmills



Toll Free 1-800-582-0470

LogRite Tools



Norwood Industries Inc.




Your source for Portable Sawmills, Edgers, Resaws, Sharpeners, Setters, Bandsaw Blades and Sawmill Parts

EZ Boardwalk Sawmills. More Saw For Less Money!

STIHLDealers.com sponsored by Northeast STIHL


Woodland Sawmills

Peterson Swingmills

 KASCO SharpTech WoodMaxx Blades

Turbosawmill

Sawmill Exchange

Michigan Firewood, your BRUTE FORCE Authorized Dealer

Baker Products

ECHO-Bearcat

iDRY Wood Lumber Vacuum Drying for everyon

Nyle Kiln Dry Systems

Chainsawr, The Worlds Largest Inventory of Chainsaw Parts

Smith Sawmill Service



Author Topic: What wire size do I need?  (Read 5512 times)

0 Members and 1 Guest are viewing this topic.

Offline Vermonter

  • Full Member x2
  • ***
  • Posts: 175
  • Age: 53
  • Location: Randolph, Vermont
  • Gender: Male
  • Best logs I'll probably ever saw-52" EWP
    • Share Post
What wire size do I need?
« on: July 15, 2005, 08:56:47 PM »
I'm almost ready to run wire to the new barn.  Wiam is coming over to finish the trench tomorrow morning.  I can't find a chart to determine the size wire I need. 
I'm running a 100 amp service to the barn, about 180' total length underground conduit.  What is the acceptable voltage drop?
The service is figured out, the utility has already set that up.
Any ideas out there?
New homestead

Offline Rockn H

  • Senior Member
  • ****
  • Posts: 917
  • Age: 49
  • Location: Hamburg (Milo) AR
  • Gender: Male
  • long way to go
    • Share Post
Re: What wire size do I need?
« Reply #1 on: July 15, 2005, 09:06:51 PM »
Is this going to be 100 amps at 220 volts to the barn with a breaker box in the barn?  Or are you going to be running a 110 volt line to the barn off of a 100amp breaker?

Offline shopteacher

  • Senior Member x2
  • *****
  • Posts: 1684
  • Age: 70
  • Location: Pa
  • Gender: Male
  • Hiking Sedona, AZ.
    • Share Post
Re: What wire size do I need?
« Reply #2 on: July 15, 2005, 09:12:31 PM »
This is what the wiring calculator states, however it doesn't say if underground is the same as overhead.

#4 copper
       
Proud owner of a LT40HDSE25, Corley Circle mill, JD 450C, JD 8875, MF 1240E
Tilt Bed Truck  and well equipted wood shop.

Offline J_T

  • Senior Member x2
  • *****
  • Posts: 1259
  • Age: 69
  • Location: Dukedom Tn
  • Gender: Male
  • Some of anything beats all of nothing Even in Dukedom Tn
    • Share Post
Re: What wire size do I need?
« Reply #3 on: July 15, 2005, 09:16:06 PM »
#1 U.S.E. Only couduit needed is on entry and exit of the ground .Here we would run a #4or #6 green as a bound wire also I use anouther ground rod at point of teremaniton and sometimes an expanion couplin. There is charts somewhere I think Close run #4 then #2 Then #1 course my memory is shot  ???Wouldn't use #4 that far myself our inspector would shoot me in the foot :D :D
Jim Holloway

Offline Vermonter

  • Full Member x2
  • ***
  • Posts: 175
  • Age: 53
  • Location: Randolph, Vermont
  • Gender: Male
  • Best logs I'll probably ever saw-52" EWP
    • Share Post
Re: What wire size do I need?
« Reply #4 on: July 15, 2005, 09:16:37 PM »
In case anybody's wondering, I do spend a lot of time thinking about how many people out there are smarter than I am.
I need the 220 for my welder, I do a little fabrication and repair.  
I was planning on splitting up my 200amp service to the house with a double disconnect meter box.

link

Now that I'm looking at it, I'm not sure it will do the job.
Is there a better way of doing this?
Oh, a new post....
Thanks shopteacher, BTW I'm no longer a shop teacher as of last week.
New homestead

Offline Rockn H

  • Senior Member
  • ****
  • Posts: 917
  • Age: 49
  • Location: Hamburg (Milo) AR
  • Gender: Male
  • long way to go
    • Share Post
Re: What wire size do I need?
« Reply #5 on: July 15, 2005, 09:18:06 PM »
Here is a site with a calculator at the bottom.

http://www.powerstream.com/Wire_Size.htm

Offline Vermonter

  • Full Member x2
  • ***
  • Posts: 175
  • Age: 53
  • Location: Randolph, Vermont
  • Gender: Male
  • Best logs I'll probably ever saw-52" EWP
    • Share Post
Re: What wire size do I need?
« Reply #6 on: July 15, 2005, 09:20:04 PM »
I have conduit the whole length because I have no intention of digging it up again (these soils are no fun) and it runs under my driveway.  I plan on the ground rod at the termination, and I have an expansion joint for where the wire pokes up from the ground.
New homestead

Offline J_T

  • Senior Member x2
  • *****
  • Posts: 1259
  • Age: 69
  • Location: Dukedom Tn
  • Gender: Male
  • Some of anything beats all of nothing Even in Dukedom Tn
    • Share Post
Re: What wire size do I need?
« Reply #7 on: July 15, 2005, 09:40:34 PM »
Did that before 300 amp base and riser then 200 and a 100 .You should still be able to run a welder ok espelley if you run larger than recomended and don't have 40 quartz lights on at the same time you are welding 8)
Jim Holloway

Offline Vermonter

  • Full Member x2
  • ***
  • Posts: 175
  • Age: 53
  • Location: Randolph, Vermont
  • Gender: Male
  • Best logs I'll probably ever saw-52" EWP
    • Share Post
Re: What wire size do I need?
« Reply #8 on: July 15, 2005, 09:50:26 PM »
Thanks for the wire calculator.  What is the maximum voltage drop recommended?
What is the designation for this type of cable?
Copper or aluminum? 
New homestead

Offline caryr

  • Full Member
  • **
  • Posts: 94
  • Age: 2017
  • Location: North Oregon Coast Range
  • Gender: Male
    • Share Post
Re: What wire size do I need?
« Reply #9 on: July 15, 2005, 10:02:58 PM »
I have always been told 5% total drop 2% in the feed circuit and 3% in the branch (so use 3%). Al is cheaper than Cu, but you need a bigger size and the conduit has to be sized correctly for which ever you choose. #2 Cu is on the edge #1/0 would be a better choice (gives you less drop). I don't have the numbers for Al handy. By the way a second ground in the barn is probably required.

Cary

Offline J_T

  • Senior Member x2
  • *****
  • Posts: 1259
  • Age: 69
  • Location: Dukedom Tn
  • Gender: Male
  • Some of anything beats all of nothing Even in Dukedom Tn
    • Share Post
Re: What wire size do I need?
« Reply #10 on: July 15, 2005, 10:13:15 PM »
Only way I'd use al wire is if it's free here they won't pass it anyway . Also on cu to those al conectors in the boxes I use Contax oxide inhibiting compound . We got four different electric Co's here with in ten miles of my house done work in all them . My 2 cents
Jim Holloway

Offline Buzz-sawyer

  • Senior Member x2
  • *****
  • Posts: 2210
  • Location: Brighton (S/W) Illinois
  • Gender: Male
  • To see it is to saw it....
    • Share Post
Re: What wire size do I need?
« Reply #11 on: July 15, 2005, 10:22:37 PM »
JT Alum. meets code nationwide what gives down there :D :D
1 or 1/0 will be good I would prefer 1/o at 180 feet and 100 amp load. Voly drop is 3.5% thats 231 v which is under 5% (recomended)
Find out if the county will allow it first....we got some of that jive up here too ;) :D :D
    HEAR THAT BLADE SING!

Offline bitternut

  • Senior Member
  • ****
  • Posts: 630
  • Age: 79
  • Location: western new york
  • Gender: Male
    • Share Post
Re: What wire size do I need?
« Reply #12 on: July 15, 2005, 10:49:14 PM »
Aluminum is fine in NY state also. You need to coat your connections with no-lox though. The NEC says its OK and they are the law as far as your insurance company is concerned. How much power does your welder need? My HH175 mig welder, Miller Dynasty 200DX and Miller plasma cutter all run fine on a 240 volt 20 amp breaker.

Use copper if you are real flush but I think it is too expensive most of the time. If it were me it would be aluminum.

Offline J_T

  • Senior Member x2
  • *****
  • Posts: 1259
  • Age: 69
  • Location: Dukedom Tn
  • Gender: Male
  • Some of anything beats all of nothing Even in Dukedom Tn
    • Share Post
Re: What wire size do I need?
« Reply #13 on: July 15, 2005, 11:40:30 PM »
Buzz here our inspectors sometimes will take it but don't like it I've noticed on the smaller al wire after a while heat even verry little will loosen the screws ??? also it will become brittle . One of the electric Co's had some trye plex they said was good . ??? Another thing underground heating and cooling creates movement and I think copper is more able to stand it . Also here you can drop the netural wire one size which I never would do because on a 110 volt a loose netural will set a fire quicker than a loose hot and cause more problems than you can think of . Most I learned the hard way. You know elect only flows on the outer most parts of the wire  ???. I think conductor wise is is gold then silver , copper then Al. If a wire heats any there is where your juse goes insted of your welder welding. ??? It an't no fun pulling wire that far once let alone twice even using elephant snot ::)
Jim Holloway

Offline caryr

  • Full Member
  • **
  • Posts: 94
  • Age: 2017
  • Location: North Oregon Coast Range
  • Gender: Male
    • Share Post
Re: What wire size do I need?
« Reply #14 on: July 16, 2005, 01:07:34 AM »
You know elect only flows on the outer most parts of the wire ???.
J_T,

The skin depth at 60Hz is sufficiently deep to ignore this for any conductor you are going to find.

I have Al for all my major feeds (>=50A) and if it is installed correctly it should not be a problem. I have had to tighten both Cu and Al at times. Just make sure you do not over tighten them!

Vermonter,

Like I mentioned earlier make sure the conduit is large enough! J_T isn't kidding that pulling wires that far in conduit can be a pain. It gets a lot worse if the conduit is too small.

Cary

Offline Don P

  • Senior Member x2
  • *****
  • Posts: 8104
  • Location: Southwestern VA
  • Gender: Male
    • Share Post
    • Calculator Index
Re: What wire size do I need?
« Reply #15 on: July 16, 2005, 01:46:50 AM »
I've seen our power guys lay the cable in the trench beside the conduit on several jobs. They put a pull rope in the 3" conduit for later if needed. A couple of weeks ago I heard the engineer tell the crew not to glue the rope to the conduit again  ::) :D. If you know the pull direction you can face the bell ends so there's less drag.
The future is a foreign country, they will do things differently there - Simon Winchester

Offline mike_van

  • Senior Member x2
  • *****
  • Posts: 1525
  • Age: 70
  • Location: Kent Ct. USA
  • Gender: Male
  • I need to edit my profile!
    • Share Post
Re: What wire size do I need?
« Reply #16 on: July 16, 2005, 07:24:34 AM »
Here in Ct., CL&P will not direct bury cable anymore, too many problems. Sched. 40 pipe, min. 3" -  On this service, I would run 1/0 Aluminum, it will have a #2 neutral wire, it will  handle anything , welder, whatever. On direct buried, the smallest stone, nick in the insulation, a few years you will be digging it up, we do at least 2 a week, sometimes more, of wire run anywhere from 5 - 20 years ago.  Makes a mess, driveways, stone walls, sidewalks. Pipe is the way to go in New England anyway.
I was the smartest 16 year old I ever knew.

Offline bitternut

  • Senior Member
  • ****
  • Posts: 630
  • Age: 79
  • Location: western new york
  • Gender: Male
    • Share Post
Re: What wire size do I need?
« Reply #17 on: July 16, 2005, 08:29:46 PM »
Vermonter you should have no trouble pulling 1/0 aluminum through that 3" pvc conduit. When I put the 200 amp underground service into my barn the power company made me run a parallel run of 4/0-2/0 triplex since the run was over 400'.  I also had to run it in 3" pvc that was glued. I pulled it myself by hand. I also dropped a 2" pvc conduit line with the phone line in the same trench. I got some polypropylene baling twine to pull through the conduit as I glued the sections together. I think the box of twine was about 7000' long. I am still tying everything up with it. Don't think I will ever run out in my lifetime.

Anyways what you need to do is make a wad of twine that is all snarled up in a ball and stuff it in the end of the first piece of conduit. Then take a stiff piece of wire that has the end wound up like the end of a spring or sewer snake. You  keep the wad of twine end a few inches back from the joint and glue a section together. Wait a minute or two and then take your piece of wire and snake it into the end of pipe to the twine ball and give it a few spins. It will grab onto the ball and you just pull it through and repeat the process. When you get done gluing up all of your sections your pull rope is in place. I then tied the rope onto a long length of 3/8" poly rope and used that rope to pull the wire through. I also pulled another length of twine through with the triplex and left it there for possible future use. Did the same thing with the phone line. By the time I got that job done I was pretty good at gluing up pipe. Once the job was done and inspected the power company took over ownership and they are responsible for any maintenance and guarantee me 240 volts at the meter which is located on the side of the barn..........not on a pole at the road.

I had a helper lining up the cable on the stuffing end when I pulled it and he also was applying lube but we found that the lube was not really needed and only used it on the beginning of the first pull. The conduit was laying on the ground next to the trench and we just flopped it over into the trench after the cable was pulled. I pulled mine with my hands but I suppose a riding lawn mower or a atv would work pretty good. Good luck with your project.


Offline Buzz-sawyer

  • Senior Member x2
  • *****
  • Posts: 2210
  • Location: Brighton (S/W) Illinois
  • Gender: Male
  • To see it is to saw it....
    • Share Post
Re: What wire size do I need?
« Reply #18 on: July 16, 2005, 10:05:17 PM »
Bitternut I have a long run to do also.
How long was your run.over 400"?
You used 4/0 for 200 amp service what was the other run........a seperate 200 amp for your barn?
    HEAR THAT BLADE SING!

Offline Vermonter

  • Full Member x2
  • ***
  • Posts: 175
  • Age: 53
  • Location: Randolph, Vermont
  • Gender: Male
  • Best logs I'll probably ever saw-52" EWP
    • Share Post
Re: What wire size do I need?
« Reply #19 on: July 16, 2005, 10:19:09 PM »
Thanks everyone for your quick responses.
Wiam and I fought the conduit into the ground today.  That's a huge step in the process.  I used 2.5", which should be big enough.  When we pull wires we:  use a shop-vac on one end, and feed a mouse (looks like a swab from a glue can) or I've heard a rag works, tied to mason's line.  Once that goes through, we pull back a measured rope and subtract what is left out.  The lube helps, as does a hand winch for the really big stuff. 
I've never sized the wire for a pull like this one.
I prefer copper also, and have needed both copper and al lugs tightened.
I can't wait until I can eliminate my extension cords.
We also used a full roll of pvc water pipe in the trench, so I will get water from the house, and a spare line just in case. 
I don't want to tell the wife I could run a phone line through it.........
New homestead


Share via delicious Share via digg Share via facebook Share via linkedin Share via pinterest Share via reddit Share via stumble Share via tumblr Share via twitter

 


Powered by EzPortal