Upgrading electrical in barn/shop

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  #1  
Old 02-23-16, 06:24 PM
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Upgrading electrical in barn/shop

Hello there, I am going to be upgrading the wiring in my barn/shop. What is there now is a joke and I'm really surprised it hasn't burned tonthe ground. I know a fair bit about electrical but am no electrician by any means so here I am lol.

I'm going to be be installing a new breaker panel in the barn to replace what is there. I have a workshop area at the front and an attached 10 stall barn with arena behind it. I'm pretty sure I've got a panel narrowed down that I will be using, I'm going to be running probably 8-10 outlets around the shop, overhead lights and would have 2 legs of 220, one hardwired to a compressor and the other an outlet for things like a welder.

Now the barn section has 10 stalls, each would have its own light and one outlet to plug in a bucket heater in the winter. And there are 3 overhead lights for the arena ad well.

My first question being what size breaker do I need to have in the house supplying the power to the barn/shop. As of now I believe it is on a 40A 2pole breaker. Should I be running something like 100A if I'm going to be running 220 out in the shop?
 
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  #2  
Old 02-23-16, 07:28 PM
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It is hard to say what you will need since you did not say how much power lights, heaters, compressors are using.
You just need to estimate what is the highest load you will put on at the same time.

100A is probably more than you need and that sounds good. Doesn't hurt to put more than you need other than costing more money for cable.

You will need to pull 4, 3 AWG wires. L1, L2, Neutral, Ground.
You also need to install grounding rod.

Unless your existing cable is pulled in a conduit and it is large enough for new cable, you will have to install new conduit.
 
  #3  
Old 02-23-16, 07:32 PM
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There really is no rule of thumb. You just need to make a list of the items that will be in use at the same time under worst case conditions, add up their power requirements, and divide by 240. That will give you a minimum starting point and you should then add at least 25% safety margin, maybe more if you envision expanding use of barn in future. The welder and compressor will be the big loads, but the other things will add up since there are quite a few of them.
There isn't a huge price jump between say, a 60 amp panel and a 120. Depending on how far away the barn is, the cost of wire may be the big item, but when you factor in all the time involved in running the wire and installing everything, it usually makes sense to go bigger.
 
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Old 02-23-16, 07:46 PM
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The wire from the house to the barn is good, it is heavy gauge outdoor underground cable that is run through conduit. But when it gets the sad excuse for a breaker box in the barn is where it gets nasty, I'm really surprised it even works, there are like 3 breakers in the whole box and one is always off cause it had a dead short somewhere where it runs out to the lean too for an outlet. There are only a few oulets that work in the shop, all the wiring is in good shape, good Romex and it's ran well but the breaker box is the big problem so that'd where I'm starting. And when the box is done and squared away I was wanting to add the 220 legs for compressor and welder, there is no 220 as of now and the barn section had no outlets and all the lights overhead and stalls are on one switch, I'm going to separate it to make the arena lights on. Switch and the stall lights all on their own separate switches so I don't have to have all the stall lights on if I want arena lights. And i just looked that building is running on a 30A breaker in the house panel as of now
 
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Old 02-23-16, 08:10 PM
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The wire from the house to the barn is good, it is heavy gauge outdoor underground cable that is run through conduit.
"Heavy gauge" is meaningless. Look on the jacket and tell us the gauge. Tell us if the cable has two or three insulated wires in addition to a ground (three or four wires total).

Note your higher voltage will be 240 volts not 220 volts.
 
  #6  
Old 02-23-16, 08:13 PM
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What size wire id run from the house to barn?

I would just install largest possible breaker and panel that existing wire can handle.
This way, you don't have problem in the future. There really isn't much difference in price for the panel and breaker. Wire is what is expensive.

Are you sure existing wiring is done correctly?
Running a thick gauge wire, but still putting it on 30A breaker doesn't sound very reasonable.
Maximum wire size that can fit under 30A breaker lug probably is 6 or 4 AWG for most breakers.

There has to be 4 conductors including ground. There has to be grounding rod at the barn.
Neutral and ground has to be separated in the panel.
You can probably get away with 3 conductors without ground if that is what you already have.

See detached building sub-panel diagram in below link. Prior to 2008, no separate ground wire was allowed.
http://www.doityourself.com/forum/el...-diagrams.html
 
  #7  
Old 02-24-16, 03:13 AM
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Oh alright, I will look and see what size is there. So I'm assuming the 4 or 6 gauge wire wouldn't be big enough?

Say I wanted to go better safe than sorry and run 100A breaker off the house, what gauge wire would I then need to pull to the barn/shop
 
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Old 02-24-16, 04:08 AM
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Ok, I looked at the cable from the house and this is what it says (UL) AWG 6 CU 3 CDR WITH AWG 10 GROUND TYPE UF-B 600 VOLTS SUNLIGHT RESISTANT

It has 2 insulated wires, red and black, I'm guessing 6 gauge? And one copper ground wire.
 
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Old 02-24-16, 05:39 AM
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(UL) AWG 6 CU 3 CDR WITH AWG 10 GROUND TYPE UF-B 600 VOLTS SUNLIGHT RESISTANT
That is UF-B 6-3 wire. Maximum breaker size you can put on that is 50A.

It may be enough depending on what you use.

It has 2 insulated wires, red and black, I'm guessing 6 gauge? And one copper ground wire.
There should be 3 insulated wires. Red, black, and White. Are you sure there is only 2?

If that wire is pulled in conduit (UF-B can be buried directly, but conduit is recommended) and conduit is big enough, you can pull 3 AWG wires for 100A.
Otherwise, you are pretty much stuck with what you have or have to start digging.

Here is ampcity chart.
http://www.cerrowire.com/ampacity-charts
 
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Old 02-24-16, 07:11 AM
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It has 2 insulated wires, red and black, I'm guessing 6 gauge? And one copper ground wire
As asked by lambition please verify there is a white neutral.
 
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Old 02-24-16, 07:12 AM
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What is the distance from the barn panel to the house panel?
 
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Old 02-24-16, 07:14 AM
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lambition

That is UF-B 6-3 wire. Maximum breaker size you can put on that is 50A.
#6 copper is 55A @ 60 deg C. so the next standard sized breaker can be used, so 60A is max size breaker. Personally, I'd limit it to 50A breaker.
 
  #13  
Old 02-24-16, 10:27 AM
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Distance from house to barn panel is around 100' just eyeballing without measuring.

I didn't see the white neutral but I will look again, in the house it has the red and black going to the 2 pole 30A breaker and the copper ground going to the ground bar. And on the barn end the red and black hook to the main breaker of the box and the ground goes to the ground bar and there is no grounding rod in the barn for that panel so I will need to install one of those as well.
I will double check that wire and make sure there is no white neutral bit I'm pretty sure it doesn't from what I've seen. Just the #6 red and black and the #10 copper ground
 
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Old 02-24-16, 10:57 AM
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If it's 6/3 then there was a neutral. Without a neutral you can get 120V or 240V, but not both, unless the neutral bar is bonded to the ground. Which is a no no in a sub-panel.
 
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Old 02-24-16, 11:06 AM
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I would go with a 60 amp breaker set for now back at the main house for the existing wiring for 100 feet to the barn.

You can install a 100 amp panel in the barn and still make the new barn lighting and receptacles a separate project from upgrading the feed to 100 amps. The latter can be deferred until you find out you don't have enouigh power for the activities you will be doing out there.
 
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Old 02-24-16, 11:21 AM
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If the neutral has been cut then the cable will have to be cut back to the neutral on both ends. (There is 6-2 with no neutral but it usually has a red jacket and is only used in Canada.)
 
  #17  
Old 02-24-16, 12:47 PM
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For now I won't need 2 legs of 240, as of now all that will be wired in is the barn lights, shop lights and shop receptacles and the hardwired 240 for compressor, it will be a long while before I will need the 2nd 240 for a recepticle for a welder, just the one for now and the rewiring of the barn to accommodate the individual outlets and independent stall light switches will be done later as well. I was just trying to paint a picture so you guys could understand the direction I'm looking to head
 
  #18  
Old 02-24-16, 12:50 PM
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As of now the barn side will run on one breaker since all it is for is lights but when I go to wire in the outlets for each stall I will most likely need to split the barn up between 2-3 breakers to handle the load, those water bucket heaters draw quite a bit of power, don't want to overload the circuit and be tripping breakers left and right
 
  #19  
Old 02-24-16, 12:54 PM
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Will probably do the overhead arena lights on one breaker, and then split the stalls up and run the 5 stalls on one side on a breaker and then the 5 on the other side on another breaker bit will need to look at load of lights and heaters for stalls and think of my worst case scenario load with all lights on and bucket heaters on so I know my circuit will handle it, yes the likelyhood of having all lights on and all bucket heaters on at the same time is slim buy I want to think worst case scenario so that the circuit is big enough to handle it safely
 
  #20  
Old 02-24-16, 02:11 PM
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I didn't see the white neutral but I will look again, in the house it has the red and black going to the 2 pole 30A breaker and the copper ground going to the ground bar.
In that case, it will have to have white neutral wire unless you are using 240V only at the barn. Neutral is required to get 120V. If it is main panel, it probably is wired with ground.
It is possible to get 120V by using ground wire and neutral, but this is incorrect wiring and not safe. It needs to be addressed if it was really done that way.

If you are ok with maximum 60A (although I recommend 50A since 6 AWG is rated for up to 55A) just replace existing sub panel with 100A and install 60A (or 50A) breaker at the main panel.
That way you can still upgrade to 100A later by replacing feeder. You probably will be ok with 60A unless you have a really big welder.
It is harder to find smaller than 100A panel with enough space anyway.

Since it is detached building and you will probably end up with more than 6 breakers in the panel, your sub-panel needs main breaker, not main lug.

Also, make sure you have grounding rod at the barn and it is attached to ground of the sub-panel. If not, install one. If your ground is soft, it will be really easy.
 
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Old 02-24-16, 02:40 PM
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You need to find the neutral before we go any further. The neutral is critical. Till you find the neutral nothing we write will help you. Please post pictures of your main breaker box with the front removed and of the breaker box at the barn. http://www.doityourself.com/forum/li...rt-images.html Please keep the width of any pictures to 1000px or less.
 
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Old 02-24-16, 02:47 PM
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Ya that's what I'm thinking, any welder I would run wouldn't be an excessively big one just for home use and I wouldn't be welding at the same time the compressor was running, in all honesty I wouldn't need to hard wire the compressor, I could just wire a pigtail ontonthe compressor so that I can be plugged into a 240 receptical that way if I'm welding I'll just simply unplug the compressor and plug in the welder and vice versa.

Yes I agree I need to sort out my feeder cable and make sure I am properly wiring the feeder cable into the new panel from the house as well as installing a ground rod for the new panel as there isn't one in place.

I believe I will go with the recommendation of a 50A breaker off the house to the new 100A panel, that way if I want to upgrade feeder cable later the panel to handle it is already in place.

I will get the feeder cable sorted out first before installing the new panel and then move forward from there.
 
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Old 02-24-16, 07:20 PM
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Ok everybody, good news, I looked again and the feeder cable has the white neutral, when I looked this morning I was in a bit of a rush and didn't see it tucked back behind the others but the feeder cable is good to go, just need to change the breaker to a 50A and install the new panel in the barn with a ground rod.

What kind of ground rod should I use and where do I hook it up to the new panel. I've never installed a panel
 
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Old 02-24-16, 07:41 PM
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The ground rod must be at least "x8'. Use a #6 wire to connect it to the ground bar.

Your new panel will probably not have a ground bar. You will need to buy and install one. Any bonding strap or screw must be removed from the neutral bar.

All grounds will go to the ground bar. All neutrals will go to the neutral bar.
 

Last edited by ray2047; 02-24-16 at 09:25 PM.
  #25  
Old 02-24-16, 07:56 PM
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Did you mean 8' ground rod? 8" seems aweful short?
What are bonding straps and screws?
 
  #26  
Old 02-24-16, 08:35 PM
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Did you mean 8' ground rod? 8" seems aweful short?
Yes it will be 8'. They don't come in 8" length.
Get copper clad instead of galvanized. They sometimes call copper ground rod, but actually is copper clad. Copper is too soft to be driven into ground and will be very expensive.
For connecting wire to ground rod, you need to use ground rod clamp.

http://www.homedepot.com/p/ERITECH-1...0UPC/202195737
http://www.homedepot.com/p/Blackburn...1-20/202907595

What are bonding straps and screws?
There usually is a screw or strap installed on neutral bar to bond it to the box (ground). This must be removed or disconnected when installed as sub panel. Many panels come unbonded from the factory and provide bonding screw for bonding if needed.

Ground bus bar is needed since you cannot connect ground to neutral bar as in main panel. This ground bar usually don't come with the panel. Ground bar will screw on to mounting hole in the panel.
 
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Old 02-25-16, 01:19 AM
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So how is the neutral bar attached to the box? Rubber mounted or something?
So the ground bar will attach to the panel and the wire from the ground rod will attach to the lug on that ground bar?
 
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Old 02-25-16, 07:01 AM
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Neutral bar is insulated from the box with plastic mounting.

So the ground bar will attach to the panel and the wire from the ground rod will attach to the lug on that ground bar?
Yes. Ground from your main panel will also attach to same ground bar.

http://ask-the-electrician.com/Pics_...8_W600-ID1.JPG
Something like this. Except this sub panel doesn't show ground from ground rod and it is main lug type.
You will need main breaker in the panel if there are more than 6 breakers.
What you can do is either buy panel with main breaker already installed, or install 50A or 60A 2 pole breaker and back feed it. Back feeding breaker has to be secured by installing screw through or clip. It is breaker and panel specific and some don't offer at all.
 
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Old 02-25-16, 07:42 AM
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Panel

Oh ok, ya the panel's I was looking at are a main breaker type that have the big main breaker at the top just like the main in the house
 

Last edited by CHRanch2015; 02-25-16 at 07:44 AM. Reason: Typo
  #30  
Old 02-26-16, 09:57 AM
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Well i picked up my new panel, ground bar and some extra breakers last night, just need my ground rod, clamp and ground wire.

What wire should inise for my 240 recepticle? Like 8-3 or 6-3?
 
  #31  
Old 02-26-16, 10:42 AM
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The wire size will need to be based on the ampacity needed.
 
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Old 02-26-16, 12:39 PM
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6-2 is like 50 or 60A isn't it. Will be using the circuit for a big 240 compressor and eventually a welder
 
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Old 02-26-16, 01:05 PM
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The sizing rules are different for compressor motors and welders, but yes #6 copper is good for at least 50A in all situations. Most of the time it can go up to 60A. On a welder or motor the breaker might be very much larger, but we would need to know the exact specs of the machine it powers.
 
  #34  
Old 02-27-16, 12:59 PM
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If I wanted to just do a 50A circuit for 240 for a conpressor and welder option what wire would I use? 6-3 right? That has two hot, neutral and grd?
 
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Old 02-27-16, 02:50 PM
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If I wanted to just do a 50A circuit for 240 for a conpressor and welder option what wire would I use? 6-3 right?
No, 6-2. You don't have a neutral on 240. You would use a NEMA 6-50 plug and receptacle.
 
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Old 02-28-16, 07:46 PM
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Oh ok, so a 240 recepticle for like a large compressor or welder uses wire with the black and red hot wires and a ground?

What is the 3 wire stuff with neautral used for?
 
  #37  
Old 02-28-16, 08:04 PM
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Things such as a stove and dryer that have controls that are 120V.
 
  #38  
Old 02-28-16, 08:05 PM
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240V only equipment (compressor and welder) only need 2 conductors to operate. 2 conductor cables will only come with 1 black and 1 white (and bare copper for ground). So, you will use both black and white wire and hot conductor. You are supposed to mark white wire by using black tape (or red tape if you have one) so that it is clear it is hot conductor not neutral. But many people will not do it.

3 conductor cables come with 1 black, 1 red, 1 white, bare copper wire. It is used for 120V/240V device that uses both 120V and 240V. For example, most cloth dryers uses 120V for control and motor, 240V for heating element.
White wire is connected to neutral, that way you can get 120V between any one hot conductor and neutral and 240V between two hot conductors.

If you want to, you can use 3 conductor cable and just don't use white wire and cap it. But that would be waste of money.
 
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Old 02-28-16, 09:16 PM
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Also note the 50 amp receptacles for stoves are different than the 50 amp receptacles for welders and compressors.
 
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Old 02-28-16, 09:52 PM
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Except for my welders where I replaced the 6-50 plug with a 10-50.
 
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