Wiring a Kiln
#1
04-21-03, 06:34 PM
Wiring a Kiln
Hi all..
Hopefully can get some advice... Looking to wire a kiln for my wife in our garage. Currently would need to go from the main panel in the basement, to the garage. About 80 ft of wire max with all the bends...
The basement has a drop ceiling so access isnt a problem for running the cable.. 50% of the run will be parallel with the joists and the other 50% is perpendicular... Nice thing is 3/4 of the joists are already drilled... It seems that it isnt that big of deal to drill the joists...
The kiln pulls 240 volts at 48 amps, and I know I need a 60 amp breaker on my main box for the kiln, and am planning to run it with #4 gauge copper wire...
The recepticle is a 6-50 recepticle so I dont think that is a problem....
I had a couple electricians come out, but there estimates seemed high ($400+) to run a cable...
I have done some wiring around the house, and the only difference I see is that it is more amps, and a bigger wire for the kiln, so I am considering DIY... Does anyone see anything I am missing??? Is this something a homeowner can tackle or do I need to quit watching "This old House"
Thanks in advance!
Tim
Hopefully can get some advice... Looking to wire a kiln for my wife in our garage. Currently would need to go from the main panel in the basement, to the garage. About 80 ft of wire max with all the bends...
The basement has a drop ceiling so access isnt a problem for running the cable.. 50% of the run will be parallel with the joists and the other 50% is perpendicular... Nice thing is 3/4 of the joists are already drilled... It seems that it isnt that big of deal to drill the joists...
The kiln pulls 240 volts at 48 amps, and I know I need a 60 amp breaker on my main box for the kiln, and am planning to run it with #4 gauge copper wire...
The recepticle is a 6-50 recepticle so I dont think that is a problem....
I had a couple electricians come out, but there estimates seemed high ($400+) to run a cable...
I have done some wiring around the house, and the only difference I see is that it is more amps, and a bigger wire for the kiln, so I am considering DIY... Does anyone see anything I am missing??? Is this something a homeowner can tackle or do I need to quit watching "This old House"
Thanks in advance!
Tim
#2
04-21-03, 07:01 PM
Member
You can do this. Make really, really, really good connections. You might want to do a demand load calculation to make sure your service size is sufficient.
#3
04-22-03, 03:59 AM
I dont imagine my service size will be a problem, even though we only have a 100 amp main breakers.. We have all gas appliances, so our draw is minimal. Asked the electricians who gave estimates, and they all thought it would be fine...
#4
04-22-03, 02:43 PM
To follow up what john said, and your later post you should be able to do this if you've done wiring before. I'd go to Homedepot and grab 100' of 6/3, the outlet, a big box for it, some proper staples, and a romex clamp for the main panel (I think you need a 1" diameter clamp for this). You pull this wire as you would a #12 or #14. The only difference is that it will fight you more since its much thicker, and heavier. Through the joist is easy, along the joist staple every 4'.
At the panel make sure you have a 1" knockout open to run the wire through. Attch the white and bare groun wires to the place(s) the rest of the whites and ground go (this might be the same place on your panel). Attach the black and red to the breaker.
At the outlet attach the black, red and bare ground to the correct screws. Cap the white off and leave it in the box. I guess you'll need to buy a small bag of large wirenuts (blue?) to cap this one wire.
At the panel make sure you have a 1" knockout open to run the wire through. Attch the white and bare groun wires to the place(s) the rest of the whites and ground go (this might be the same place on your panel). Attach the black and red to the breaker.
At the outlet attach the black, red and bare ground to the correct screws. Cap the white off and leave it in the box. I guess you'll need to buy a small bag of large wirenuts (blue?) to cap this one wire.
#6
04-22-03, 03:05 PM
Ahhh just saw your reply to my other post... Actually home depot does carry 6/2 and it is about 1/3 cheaper.. Since I am running about 60-70 feet I would prefer to run 4 gauge wire and that is proving more difficult to find... I really dont know much bout running conduit so I would prefer to stick to the flexable nm wire...
#7
04-22-03, 04:22 PM
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Was the 6-50 receptacle original to the kiln? Generally the breaker size should match the wire size which should match a receptacle (when it is the only one on the circuit). If it draws 48A full load, then 60A is a good size breaker. But, it should be connected to #6 awg copper and a 60A receptacle.
#8
04-22-03, 05:35 PM
Well, I stand corrected. I've never used anything bigger than 10/2, after that it has always been 8/3, 6/3, 2/3 etc. OK, I guess SE cable is ##/2, but that doesn't really count.
If HD has the 6/2 I'd go with that. At 80' for 50 amps the voltage drop on the #6 is about 3.8 volts. For #4 it would be 2.4 volts. So while 1.4 volts isn't 0, its not alot either.
Since you could find 6/2, maybe the local supply house would carry 4/2. Or as Texsparky said you could get either #4 copper SE (service entrance cable) or #2 Aluminum. HD should carry a #2 AL SE type cable (the kind with 2 conductors, and the third ground conductor braided around the the outside). If you go with the AL wire make sure you get NOALOX or its equivelent to squirt into the connection points (breaker, outlet, etc). If not the AL will oxidize (rust) and cause you problems down the road.
If HD has the 6/2 I'd go with that. At 80' for 50 amps the voltage drop on the #6 is about 3.8 volts. For #4 it would be 2.4 volts. So while 1.4 volts isn't 0, its not alot either.
Since you could find 6/2, maybe the local supply house would carry 4/2. Or as Texsparky said you could get either #4 copper SE (service entrance cable) or #2 Aluminum. HD should carry a #2 AL SE type cable (the kind with 2 conductors, and the third ground conductor braided around the the outside). If you go with the AL wire make sure you get NOALOX or its equivelent to squirt into the connection points (breaker, outlet, etc). If not the AL will oxidize (rust) and cause you problems down the road.
#9
04-22-03, 05:59 PM
Member
With any of these cables, you do not need to run it through the joists in your basement. Code allows cable this large to simply be stapled to the bottom of the joists. That should make your job much, much easier.
#10
04-22-03, 06:16 PM
QUOTE]Was the 6-50 receptacle original to the kiln? Generally the breaker size should match the wire size which should match a receptacle (when it is the only one on the circuit). If it draws 48A full load, then 60A is a good size breaker. But, it should be connected to #6 awg copper and a 60A receptacl[/QUOTE]
I think Handy Ron has a good point. See Table 210.21(B)(3). Someone please correct me if Im wrong, but couldnt he use #8 with a 50a breaker on this since its a single receptacle, with no other loads.
I think Handy Ron has a good point. See Table 210.21(B)(3). Someone please correct me if Im wrong, but couldnt he use #8 with a 50a breaker on this since its a single receptacle, with no other loads.
#11
04-22-03, 06:17 PM
The only reason I was thinking the 4 gauge cable, is the kiln manufacture recommended at over 50' to use a bigger cable.. Sounds like they may be just overly pesstamistic since a 1.4 voltage drop doesnt sound like it would be a problem.
The 6/50 recepticle is what the kiln comes with on the male end. So I was just matching it up. The kiln only uses 48 amps, but it requires a 60 amp breaker.
Didnt consider going below the joints, but I am also considering doing something with the drop ceiling so I may just go through the joists so I dont have a problem down the line...
HD had the 6/2 cable online, but have yet to check the store. If I did just get the 6/3 cable, do I even connect the neutral to the breaker, or just cap off both ends?
Thanks,
Tim
The 6/50 recepticle is what the kiln comes with on the male end. So I was just matching it up. The kiln only uses 48 amps, but it requires a 60 amp breaker.
Didnt consider going below the joints, but I am also considering doing something with the drop ceiling so I may just go through the joists so I dont have a problem down the line...
HD had the 6/2 cable online, but have yet to check the store. If I did just get the 6/3 cable, do I even connect the neutral to the breaker, or just cap off both ends?
Thanks,
Tim
#14
04-22-03, 07:10 PM
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You would cap the unused conductor at both ends.
marcerrin
210.21(B)(3) is for duplex recepts or more outlets on one circuit.
Since this is a dedicated single recept on this circuit, I applied 210.21(B)(1) indicating that the ampere rating of the recept shall be not less than that of the branch circuit. So, if the recept is 50A, then the circuit should be 50A.
Since the load of the kiln is probably similar to an oven, where it is considered non-continuous, then a 50A recept might be ok for this application. I would not use a 60A breaker with a 50A recept.
marcerrin
210.21(B)(3) is for duplex recepts or more outlets on one circuit.
Since this is a dedicated single recept on this circuit, I applied 210.21(B)(1) indicating that the ampere rating of the recept shall be not less than that of the branch circuit. So, if the recept is 50A, then the circuit should be 50A.
Since the load of the kiln is probably similar to an oven, where it is considered non-continuous, then a 50A recept might be ok for this application. I would not use a 60A breaker with a 50A recept.
#15
04-25-03, 09:42 AM
The kiln already comes with the 6-50 plug installed on it, so I guess that is what the Manufacture is expecting. They also spec a 60 amp. Is this a problem with the installation? The Kiln only draws 48 amps max, but I guess they want the heaver breaker for some flexibility...
#16
04-25-03, 12:40 PM
Handyron,
Your right, I read the whole page but gave the wrong referance. In any case we come to the same conclusion.
I have another question though, is this unit used?
Your right, I read the whole page but gave the wrong referance. In any case we come to the same conclusion.
I have another question though, is this unit used?
