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How To Pull Wire Through Conduit

Pulling wire or cable through conduit is a fundamental skill needed for electricians or anyone who installs wiring systems.  Conduits provide protection for electrical wires, shielding them from damage and aiding with maintenance. However, the way in which you pull the wire through the conduit can be a complex process and needs to be done in an efficient and safe manner.

Planning & Considerations

Before you start pulling cable, you will want to consider the following:

How long is the conduit run that you need to pull the wire through?
Shorter runs are generally easier to pull than longer runs. The longer the run, the more friction will be created as you pull the wire through the conduit. This friction, if high enough, can damage your wires and expose the conductor, which can cause arcs, sparks, or shorts. Additionally, your run length may limit which method can be used. Rods, for example, may not be an option for extremely long runs.

How complex is the conduit path?
Are there any obstacles in the path? How many bends are there and what are the angles of the bends? Obstacles and bends create more friction where the wire rubs against them. With bends, the larger the angle of the bend, the more friction there will be at the inside of the bend. That friction can lead to wire damage or can cause wires to get jammed.  Additionally, for complex or long paths, it may be helpful to have a partner to assist you with the pull.

What type of conduit will you be pulling your wires through?
Different types of conduits have different properties that need to be considered. For example, HDPE Conduit is flexible, and could have additional twists or bends that you wouldn’t get with straight EMT or PVC conduit. Straight conduit often has sharper bends than a flexible metallic or HDPE conduit. Corrugated conduit will create more friction than smooth conduit and any joints in the conduit (especially with PVC) can cause friction or jam up your wires.

What size is the conduit?  
Conductors in your wire will generate heat, and if there isn’t enough space in your conduit, you run the risk of exceeding the insulation heat limits, which can lead to that insulation melting and exposing your conductors. The NEC sets standards that must be followed to determine how much space in your conduit can be taken up by your wires. A single conductor can fill 53% or less of a raceway, 2 wires can fill up to 31%, and more than 2 can fill no more than 40%. Refer to our Conduit Wire Fill Charts & Tables page for more information.  

How many cables are included in the wire pull?
The more wires you pull at a time, the greater the friction. Jams are typically more common when multiple wires are being pulled. If enough tension is applied, the wires could be damaged or even break, causing conductors to be exposed.

Are there existing wires or cables already in the conduit?
If existing wires will need to stay in place, they must be considered as you determine how much room is left in the raceway for your pull. If the existing wires are no longer needed, you will need to remove them, but may be able to put them to use for your run. (More on that in a bit).

Additional Cable Pulling Materials 

Along with the tools described in each of the methods, the following items can make pulling wire through conduit much easier.

  • Pulling Lubricant.Regardless of the pulling method, using a wire-pulling lubricant is recommended to reduce friction and ease the cable's passage through the conduit. Lubricants can make the pulling process smoother and minimize the risk of damaging the cable insulation.
  • Mesh Socks are specialized devices designed to attach to the cable and provide a secure grip for pulling. These are particularly useful when dealing with multiple cables or when the cable's surface is not smooth, as they prevent damage to the cable during the pulling process.


Wire Pulling Methods

Once you’ve considered the above, you can determine what method you will use to pull the cable through the conduit. Below are some of the typical pull methods.


Manual Pulling

This method involves physically pulling the cable through the conduit by hand.

Best for:

  • Short, straight runs
  • Single wires

Advantages:

  • No additional tools required
  • No setup time

Disadvantages:

  • Will require more care to ensure cables do not get twisted or damaged
  • Cannot be used for long or complex runs

Process:

  1. Inspect conduit for any obstacles that could damage cable during pulling and ensure conduit is clear of any debris.
  2. If the conduit already contains a wire that is no longer needed, you can tie the new wire to the end of the existing wire, then use the old wire to pull the new wire through the conduit.
  3. If there is not an existing wire to use, as in the step, thread the wire through the conduit and push the wire through.
  4. Once the cable has been successfully threaded through the entire conduit path, trim any excess length and strip the wire ends. Connect the cable to the appropriate electrical boxes, outlets, or termination points as required.
  5. Verify that all connections are secure and correctly terminated. Conduct necessary tests to ensure the electrical system functions as intended.


Pull String/Rope/Tape

For longer and more challenging runs, a pulling rope or string can be used. The rope is first pulled through the conduit, and then the cable is attached to the rope and pulled back through the conduit.

Best for:

  • Longer and more complex runs

Advantages:

  • Can do multiple cable runs at one time
  • Can pull heavier cables
  • Flexibility allows it to navigate bends and obstacle
  • Can be used for longer pulls
  • Relatively inexpensive
  • Minimal equipment needed
  • Lightweight and easy to transport

Disadvantages:

  • Limited weight capacity
  • Risk of snags on rough surfaces which may damage wire
  • Limited lifespan – will wear/fray over time
  • Not recommended for multiple cables simultaneously as cables can get twisted
  • Can be physically demanding, especially for long runs


Process:

  1. Inspect conduit for any obstacles that could damage cable during pulling and ensure conduit is clear of any debris.
  2. Apply pulling lubricant to reduce friction.
  3. Attach the cable to the pulling end securely. You can use electrical tape or a wire pulling grip to create a tight connection between the cable and the pulling device.
  4. If you have a partner to work with, one person feeds the cable into the conduit from the starting point while another person pulls the cable from the other end. Be sure to communicate throughout to ensure that consistent, steady force is used.
  5. Use gentle back-and-forth movements and steady pressure to guide the cable around bends and through tight spots.
  6. For longer runs or more challenging conduit paths, consider pulling the cable in stages. Stop periodically to ensure the cable is not getting snagged or encountering any issues. Make any necessary adjustments before continuing the pull.
  7. Once the cable has been successfully pulled through the entire conduit path, trim any excess length and strip the wire ends. Connect the cable to the appropriate electrical boxes, outlets, or termination points as required.
  8. Verify that all connections are secure and correctly terminated. Conduct necessary tests to ensure the electrical system functions as intended.


Fish Tape

A fish tape is a long, flexible, and narrow tool made of steel or fiberglass. The tape is inserted into the conduit, and the cable is then attached to the fish tape and pulled through the conduit by guiding the tape along the desired path.

Best for:

  • Short and medium length runs, even with complex paths

Advantages:

  • Relatively inexpensive
  • Simple setup
  • Minimal equipment needed
  • Flexible and able to move around bends and obstacles

Disadvantages:

  • Limited distance – need a fish tape that is longer than the actual run
  • Requires manual effort.
  • Not recommended for multiple cable pulls
  • Can damage cable if excessive force is used during the pull
  • Not recommended for heavy cables

Process:

  1. Inspect conduit for any obstacles that could damage cable during pulling and ensure conduit is clear of any debris.
  2. Apply pulling lubricant to reduce friction.
  3. Securely attach the end of the wire you want to pull to the end of the fish tape.
  4. Insert the free end of the fish tape into the conduit from the starting point where you want to begin pulling the wire.
  5. Insert the free end of the fish tape into the conduit from the starting point where you want to begin pulling the wire.
  6. One person should begin pulling the fish tape from the other end of the conduit while the person at the starting point feeds the fish tape into the conduit.  As the fish tape progresses through the conduit, guide it carefully to navigate bends, corners, and any obstacles. Use gentle back-and-forth movements to help the fish tape move smoothly and periodically check for snags.
  7. Once the fish tape has been pulled through the entire conduit path, detach the wire from the fish tape. Make sure the wire is securely in place and properly aligned within the conduit.
  8. Trim excess length and strip the wire ends. Connect the cable to the appropriate electrical boxes, outlets, or termination points as required.
  9. Verify that all connections are secure and correctly terminated. Conduct necessary tests to ensure the electrical system functions as intended.

Duct Rodder

This specialized tool is designed for pulling cables through conduits and ducts. Conduit rodders are particularly effective for long conduit runs, as they can cover considerable distances without requiring intermediate access points. They are also highly flexible, allowing them to navigate through bends, curves, and obstacles in the conduit easily.

Best for:

  • Long and complex conduit runs

Advantages:

  • Can cover considerable distances without requiring intermediate access points
  • Highly flexible and can maneuver around bends and obstacles
  • Saves on time and labor
  • Can be used for multiple runs simultaneously and work with bundles

Disadvantages:

  • Initial cost can be prohibitive for smaller one-off projects
  • Not recommended for small-diameter conduits
  • Requires training to effectively operate
  • Size of rodders can increase challenges for transport and storage

Process:

  1. Inspect conduit for any obstacles that could damage cable during pulling and ensure conduit is clear of any debris.
  2. Apply pulling lubricant to reduce friction.
  3. Start by securely attaching the end of the wire you want to pull to the end of the duct rodder. Use a wire pulling grip or other suitable connectors to create a tight and secure connection.
  4. Insert the free end of the duct rodder into the conduit from the starting point where you want to begin pulling the wire.
  5. As the duct rodder progresses through the conduit, guide it carefully to navigate bends, corners, and any obstacles. Use gentle back-and-forth movements and steady pressure to help the duct rodder move smoothly. Periodically check for snags and backtrack/adjust alignment for a clear path.
  6. Keep pushing the duct rodder through the conduit until it reaches the other end.
  7. Trim excess length and strip the wire ends. Connect the cable to the appropriate electrical boxes, outlets, or termination points as required.
  8. Verify that all connections are secure and correctly terminated. Conduct necessary tests to ensure the electrical system functions as intended.


Compressed Air / Conduit Mouse

For longer and larger-diameter conduits, a vacuum or compressed air system can be employed. A vacuum system sucks a foam or rubber carrier (called a conduit piston or conduit mouse) through the conduit, carrying the cable along with it. Similarly, compressed air can propel a carrier through the conduit.

Best for:

  • Short runs with complex conduit path

Advantages:

  • Quick and efficient, which reduces installation time
  • Can work with multiple conduit sizes
  • Eliminates tension on the cable during the pull
  • Can also clean debris as it moves through the conduit

Disadvantages:

  • Limited distance
  • Cannot be used with delicate or sensitive cables because of risk of damaging wire insulation
  • Air leaks in the conduit can reduce effectiveness of this method
  • Cannot be used with conduit that already has wire installed

Process:

  1. Inspect conduit for any obstacles that could damage cable during pulling and ensure conduit is clear of any debris.
  2. Apply pulling lubricant to reduce friction.
  3. Attach a pulling device, such as a pulling sock or a cable grip, to the end of the cable you want to pull through the conduit. Ensure it is securely fastened to prevent it from detaching during the pull.
  4. Connect the compressed air source to the conduit. Use a suitable air hose and secure it tightly with appropriate fittings to prevent air leaks.
  5. To ensure that the air pressure is effective, temporarily seal the opposite end of the conduit where the cable will exit. You can use duct tape, a foam rubber plug, or another suitable seal.
  6. Turn on the compressed air source to apply pressure to the conduit. The air pressure will push the cable through the conduit, propelling it towards the sealed end.
  7. As the cable moves through the conduit, keep an eye on its progress and adjust the air pressure if necessary. Avoid excessive pressure, as it may damage the cable or cause it to become entangled.
  8. Once the cable reaches the sealed end of the conduit, be ready to catch and guide it when you remove the temporary seal.
  9. Trim excess length and strip the wire ends. Connect the cable to the appropriate electrical boxes, outlets, or termination points as required.
  10. Verify that all connections are secure and correctly terminated. Conduct necessary tests to ensure the electrical system functions as intended.

Fishing Weight

A fishing weight, typically made of lead or another heavy material, is attached to the cable, providing additional weight to help guide the cable through the conduit.

Best for:

  • Short and uncomplicated conduit runs with lighter cables

Advantages:

  • Low cost
  • Simple setup with minimal equipment

Disadvantages:

  • Limited pulling force
  • Limited pulling distance
  • Prone to getting hung up on snags or obstacles that can damage cables
  • Cannot be used with heavy cables

Process:

  1. Inspect conduit for any obstacles that could damage cable during pulling and ensure conduit is clear of any debris.
  2. Apply pulling lubricant to reduce friction.
  3. Securely attach the fishing weight to one end of the wire you want to pull. You can use electrical tape or a wire pulling grip to create a tight and secure connection.
  4. Insert the free end of the wire into the conduit from the starting point where you want to begin pulling.
  5. Hold the fishing weight in one hand and gently feed the wire into the conduit with the other hand. Allow the fishing weight to pull the wire through the conduit.
  6. As the fishing weight pulls the wire through the conduit, steady the fishing weight and guide the wire to navigate bends, corners, and any obstacles. Use gentle back-and-forth movements and steady pressure to help the wire move smoothly. Periodically check for snags and backtrack/adjust alignment for a clear path.
  7. Keep pulling the wire with the fishing weight until it reaches the other end of the conduit.
  8. Once the wire has been pulled through the entire conduit path, detach the wire from the fishing weight.
  9. Trim excess length and strip the wire ends. Connect the cable to the appropriate electrical boxes, outlets, or termination points as required.
  10. Verify that all connections are secure and correctly terminated. Conduct necessary tests to ensure the electrical system functions as intended.


Motorized Pulling Machine

Motorized pulling machines apply constant force to pull the cable through the conduit smoothly and efficiently. They are capable of handling heavy loads and can save time and effort compared to manual methods.

Best for:

  • Industrial or commercial applications with long runs and heavy-duty cables

Advantages:

  • Consistent tension is applied to the pull, reducing the risk of damaging wires during the pull
  • Can do multiple cable runs at one time and pull bundles
  • Saves time and labor with their efficiency
  • Often have adjustable speed and pull force settings, which allow them to be used for multiple cable sizes and conduit types

Disadvantages:

  • Pulling machines can be relatively expensive, especially for high quality pullers
  • Additionally, maintenance of the pulling machine can add to long term cost
  • Size and weight of machines makes them less portable than some other options
  • Require a power source to function
  • Require specialized training for operators to ensure safe operation

Process:

  1. Inspect conduit for any obstacles that could damage cable during pulling and ensure conduit is clear of any debris.
  2. Apply pulling lubricant to reduce friction.
  3. Attach one end of the wire you want to pull to the pulling machine. Most pulling machines have a winch or capstan designed to hold the wire securely.
  4. Insert the free end of the wire into the conduit from the starting point. If the conduit run is particularly long or complex, it may be helpful to use a fish tape or pull rope to guide the wire through the initial bends.
  5. Turn on the motorized pulling machine to initiate the pulling process.
  6. As the pulling machine moves the wire through the conduit, steady the wire and guide it to navigate bends, corners, and any obstacles. Use gentle back-and-forth movements and steady pressure to help the wire move smoothly. Periodically check for snags.
  7. Keep the pulling machine powered on and allow it to continue pulling the wire through the conduit until it reaches the other end.
  8. Once the wire has been pulled through the entire conduit path, detach it from the pulling machine. Make sure the wire is securely in place and properly aligned within the conduit.
  9. Trim excess length and strip the wire ends. Connect the cable to the appropriate electrical boxes, outlets, or termination points as required.
  10. Verify that all connections are secure and correctly terminated. Conduct necessary tests to ensure the electrical system functions as intended.

 

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