Have you ever seen a wire pull become a disaster? This doesn't need to happen. Several wire pulling tools and methods exist, but "pull by fishtape" is the most common. Sometimes, this fishtape breaks free of the wires during the pull. Always, this is due to improper wire pulling methods. Here's how to make sure your wire pull is successful.
Let's see how to use the fishtape properly. Some preliminary guidelines are necessary, here. First, don't jam the fishtape through the wireway. Doing so puts kinks in the tape and makes it difficult to pull the wire.
Second, put some wire lubrication on the first few inches of the tape. This will help it slide over the edges of fittings and around the first bend or two.
Suppose you can't get the fishtape through, even though you took the precautionary steps noted above. What do you do, now? Well, you have three options.
First option: Pull the tape back out and cover the hook with phasing tape; then coat the phasing tape with lubricant. On short pulls, this works fine.
But, suppose you're "almost there" and don't want to pull the tape all the way back out. Here, you have two more options.
Second option: Run a second tape in from the other end and manipulate it to connect with the first tape, as shown in Fig 1 (in the original article). Suppose you can't hook the tapes together. Here's what you can do.
Third option: Make some loops of stiff wire and tape them in place, as shown in Fig 2 (in the original article). Then, let the first tape grab on to one of these.
Now, attach the wire to the fishtape. For the best chance of pulling it through, here's how you should do this.
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First, strip 6 in. of insulation off each conductor.
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Second, fasten one conductor to another, by tightly wrapping the first conductor around the second, as shown in Fig. 3.
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Third, wrap only one conductor into the hook of the fishtape, as shown in Fig. 4 (in the original article).
A common mistake is to wrap all the conductors into the fishtape hook. This makes one big knot that will likely come apart; or even get stuck so you can't move it either direction.
Remember: fasten one conductor around the fishtape hook. Don't tape the joints individually. Tape over the open end of the fishtape hook, then tape the whole assembly, as shown in Fig. 5 (in the original article).
With one person pushing and another pulling, you should be able to pull the wires through. The person who is pushing should smear lubricant on the wires as they enter the wireway, until the run is well underway. You may need to use needle nose pliers to get the end of the fishtape out.
These techniques ensure an easy pull for most sizes of wire. Unless you are pulling extremely large conductors (such as 500 kcmil), you shouldn't need to use anything other than elbow grease or a good fishtape puller to complete the pull.
Here are three important rules in wire pulling:
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Make sure your wiring does not exceed the wireway fill specified by the NEC. You'll find the appropriate tables in NEC Chapter 9.
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Use the correct wireway cutting, deburring, and assembly techniques. This will eliminate many of the obstructions that make pulls hard to complete.
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Pull the wires only after you complete the wireway. This will save you time and prevent damage to the wiring.