Electrician/GC Pulling 13 #8 conductors

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JustCallBen

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Building contractor
I guess I need to qualify myself before I can request information. I am an electrician and an electronics technician. I am a general contractor in the car wash trade. I build, repair and remodel car washes in Southern California. I have never run this many large conductors in one conduit so I ask for advice.

I have a job coming up where we need to pull 13 #8 conductors through 2" PVC conduit. Total run is about 90 feet with 3 90s. I can and will add pull boxes at critical junctions based on best advice.
Basically we go from the end point up 10 feet, 90 turn, pull 55 feet, 90 turn, pull 16 feet, 90 turn, 5 feet into control center. Wire will be cut into 13-100' rolls.
What tools other than lube and pull rope would be needed to get this done? I have a 12v winch I can use as well.

Hopefully I have adequately qualified myself to be able to request information and assistance here.
 
Yes we like to know how you're related to the electrical industry before posting. Since you're an electrician you're good to go. Please update your profile occupation to reflect this.

In answer to your question the pull you've outlined should be rather easy if it's setup properly. You'll need a high quality rope. What was your idea for attaching the conductors to the rope?
 
Well that was one of the main questions. What to attach the conductors to. In smaller gauges I have used the Chinese handcuffs but not sure how that would work with 13 larger conductors. Would each of them have its own handcuff or how else does that work?
 
80% of the pull is in the setup. I would tape them in groups of 2, then all together, with a basket grip, and tape over all, lots of lube and help to keep from getting kinks
 
I would use a 3/8" rope. Your conduit is plenty big enough and only 3 - 90's. Should be an easy pull. Either use a Kellems grip like described above or simply strip the conductors back a little and cut off a few strands to make the head smaller.
 
I learned to strip several inches of each wire, peel back approx. three outer strands on opposite sides, cut away the rest of the strands, then pass each wire's two groups of strands through the eye of the rope in opposite directions, and tape the entire bundle of smoothed strands neatly.

The finished taped head should end up being no thicker than the bundle of wires themselves. Have a helper to feed the wires, keeping them in line by combing with the fingers, and feeding only as fast as you pull. Tape will only make the bundle stiffer. You shouldn't need any pull boxes.
 
Uh, nobody has mentioned the required de-rating. With 10 to 20 current carrying conductors in one conduit, you must derate the circuits by 50%. Assuming you are using THHN copper wire, that brings the ampacity of each circuit down to 25 amps. Since 25A breakers and fuses are a standard rating, that's as high as you can go. AND the circuit must be designed 125% greater than the load. That brings you down to 20 amps.

Do you have any circuits that will draw more than 20 amps?
 
TwoBlocked said:
Uh, nobody has mentioned the required de-rating. With 10 to 20 current carrying conductors in one conduit, you must derate the circuits by 50%. Assuming you are using THHN copper wire, that brings the ampacity of each circuit down to 25 amps. Since 25A breakers and fuses are a standard rating, that's as high as you can go. AND the circuit must be designed 125% greater than the load. That brings you down to 20 amps.

Do you have any circuits that will draw more than 20 amps?
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You raise a valid concern. Carwash says lots of motors to me so that will change the derating details and breaker size limits. In addition there could be non-coincidental loads. It won't just be a simple matter of this is the derated ampacity and so the breaker will be X.
Need a lot more details to make a judgement on what the OP is doing.
 
TwoBlocked said:
Uh, nobody has mentioned the required de-rating. With 10 to 20 current carrying conductors in one conduit, you must derate the circuits by 50%. Assuming you are using THHN copper wire, that brings the ampacity of each circuit down to 25 amps. Since 25A breakers and fuses are a standard rating, that's as high as you can go. AND the circuit must be designed 125% greater than the load. That brings you down to 20 amps.

Do you have any circuits that will draw more than 20 amps?
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Truly I haven't done my calculations yet. They are intermittent loads at typically 24A 3ϕ. I don't understand why you have to use the same derating for 3 conductors and 15 conductors in a given space. I guess the brainiacs are at work there. If it's a problem with derating, I may go to troughs with SOOW instead.
 
JustCallBen said:
Truly I haven't done my calculations yet. They are intermittent loads at typically 24A 3ϕ. I don't understand why you have to use the same derating for 3 conductors and 15 conductors in a given space. I guess the brainiacs are at work there. If it's a problem with derating, I may go to troughs with SOOW instead.
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3 conductors in a conduit more the 24 inches long there is no derate. You put 15 conductors in a conduit more than 24 inches long you have to derate by 50%.
 
qcroanoke said:
3 conductors in a conduit more the 24 inches long there is no derate. You put 15 conductors in a conduit more than 24 inches long you have to derate by 50%.I'
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I'm three strong beers in to Thursday Night Football (Go Chiefs!!!) and I want to say something rude right now but I'm new on the board so I'll be nice. Thanks for letting me know what I already found. By the way, who does a 24-inch run and even thinks about derate? Probably the same genius that came up with AFCI that trips when you plug in any PWM device.
 
JustCallBen said:
Truly I haven't done my calculations yet. They are intermittent loads at typically 24A 3ϕ. I don't understand why you have to use the same derating for 3 conductors and 15 conductors in a given space. I guess the brainiacs are at work there. If it's a problem with derating, I may go to troughs with SOOW instead.
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You still have to derate in a cable
If more than three current carrying conductor
 
JustCallBen said:
I'm three strong beers in to Thursday Night Football (Go Chiefs!!!) and I want to say something rude right now but I'm new on the board so I'll be nice. Thanks for letting me know what I already found. By the way, who does a 24-inch run and even thinks about derate? Probably the same genius that came up with AFCI that trips when you plug in any PWM device.
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You certainly don't need to take offense. There are some really sharp guys here that tend to look at things from a Code perspective and there are immediate red flags that go up when bundling is concerned. When you mention 24 amp of intermediate motor load on conductors rated 27 amps and using SOOW as a wiring method it does raise the attention of some Code gurus especially when the OP concerns a wire pull.
 
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