Electrical Equipment and Installations
It’s important to align your tool investment to the task at hand. Let’s look at the innovations that enable electricians to be more productive on residential and commercial jobsites.
Conduit Cutters and BendersTo bend and cut, thread, and connect wires through metallic, non-metallic, and plastic conduit, special tools are needed. Traditionally these tools have been manual or corded. But in recent years, tool manufacturers have introduced a wide range of battery-operated tools that perform the same functions.
Conduit Benders allow you to easily make smooth, even bends. Most benders allow you to craft smooth radiuses. But for special applications, you might consider purchasing an off-set bender. It’s important to match the bender size to the conduit’s diameter. There are some conduit benders that are designed for multiply diameters.
Conduit Cutters are specialty tools to custom cut conduit. Some conduit cutters are also pipe cutters and used for simple operations. These tools are equipped with reamers that deburr and chamfer the fresh cut conduit lips. The smoothed surface prevents damage to wires and cables when they are pulled through conduit.
Conduit Threaders are special pipe threaders that use unique dies designed for conduit. They enable clean threads without distorting the conduit.
Conduit Connectors (ENT, LFNC, Plastic PVC) join conduit sections by applying a conduit solvent cement to fittings. IMC (Intermediate Metal Conduit) connectors are joined by compression, and stainless-steel RMC (Rigid Metal Conduit) is used in corrosive areas and may exceed the limitations of aluminum, fiberglass, rigid steel, PVC, & PVC-coated conduit.
This tool works great when running conduit through steel studs in commercial settings. It eliminates the hassle of inserting metal conduit through steel studs. Punches can handle up to 20-gauge steel and insert stud bushings to protect the conduit and cable from sharp metal edges. You’ll also need a conduit bender. A manual model will work fine unless it’s a large job; then you’ll want a power bender.
Tools to Install Cables in ConduitOnce the conduit is in place, the next step is having the right tools to install your cables or wires. You must have the right combination to prevent over-pulling, stretching or causing damage during the installation.
Make sure that you have plenty of room before starting. You’ll need to plan for the reel jacks, playout trees, and enough room to splice cable if necessary. Store reels where they will be safe from both
Store reels on hard surfaces, as this will prevent the flanges from sinking and the reel weight from resting on the cable. Only stack light reels directly on top of each other using two-by-four spacers or pallets under the bottom flange. For heavier reels, store on hard surfaces with the flanges vertical. Storing heavier reels with the flanges horizontal will put too much weight on the cable and can cause damage.
Pulling Best Practices
- Pull in a direction that will require the lowest amount of pulling force.
- Plan several shorter pulls rather than fewer longer pulls.
- Locate the puller as close to the end of the conduit as possible to minimize the amount of exposed rope under tension.
- Place each component so that the pulling forces are used effectively.
- Verify that each component has the proper load rating.
- Inspect the structural supports. Verify that they have enough strength to withstand the maximum forces that may be generated.
- Locate the puller so that it is close to the conduit. Rope, cable, or connectors can break under tension, causing the rope to whip violently.
Once everything is in place you can start the installing your wire.
7 Steps for a Successful Wire Installation
Coiled around a donut-shaped reel, fish tape is a flat, thin, long wire made from steel, nylon, or fiberglass (which offers the best performance and durability). However, a steel tape can push and pull with more strength before bending.
Recent innovations allow fish tape pay out and reel in more smoothly. There are battery-powered fish tapes and power fishing systems that use high-pressure air.
Fish sticks and other wire pulling rods can be made from a variety of materials and even have specialized accessories such as lubricants, LED lights, cameras, and glow sticks that are visible in ceilings, subfloors, and walls.
Rods are different from fish tape in that rods have shorter lengths of material that are not used in conjunction with a reel. Fish tape and reels are great for long conduit runs while rods are better for fishing up and down wall cavities and across other hidden areas where rigidity gives you an edge. Rods can be spliced together for greater lengths.
Conduit pistons are very effective for high-end residential and commercial jobs where new wires must be run through long lengths of conduit. Pistons use airbags to remove obstructions such as bent casings or material.
2. Installing Conduit Rope
Once you have established the pulling path, you’ll need to replace the fishtape with a rope strong enough to pull the wire through the conduit. It’s important to size the pulling rope so that it absorbs the stress of passing through the conduit. For most situations, you want to select a rope that is four times as strong in tensile strength as compared to the wire it will pull.
Crimpers are tools used to make cold weld joints between two wires or a wire and a connector, such as lugs. Ideally, the electrical and mechanical properties of the weld joint are as strong as the parent materials.
Crimping tools are sized according to the wire gauges (using AWG - American Wire Gauge) they can accept. Some come with interchangeable die heads that allow for a wider range of wire sizes and connectors.
Hand or hammer crimpers are relatively cheap and may be your best options if you only crimp occasionally.
Hydraulic and automated crimpers (e.g. battery powered) are more expensive but will prevent strain and injury due to repetitive crimping operations. Indent style crimps are usually used for crimping fine stranded and compacted conductors. Hexagonal style compression crimps, the most common type of crimp, create strong mechanical connections.
4. Handling the Cable
It is important that the wire conductor isn’t damaged in any way. When handling large reels consider using a reel lifter. These devices hold the spool in an optimal ergonomic position for payout. It features adjustable load beams, which are helpful when handling reels of different sizes, and it stores easily with built-in housing for the hook and chain assemblies. Some reel lifters can hold multiple reels of cable on a single master unit, allowing for additional versatility along with an even payout.
Prior to placing the cable in the conduit, electricians use special brushers or swabs that are pulled through the pathway. They remove any debris that may have been introduced in the pathway.
There are several types of tools that grip the wire that is being pulled through the conduit, these types include long pulling grips, short pulling grips, set clamp type pulling rips.
And use a conduit lubricant. Select a product that is made from material that is non-corrosive to aluminum, copper, PVC, and galvanized steel. Most lubricants are, the water-soluble, drying to a non-toxic lubricating powder after application. Many of the newest brands are 100% non-toxic and eco-friendly.
6. Wire Pulling
Select a wire puller that matches the site conditions and the anticipated pulling stress.
Commercial pullers range in capacity from 2,000 lbs to 10,000 lbs. Try to select a puller that features an on-board force gauge that allows you to monitor the strain being placed on the wire. Another important feature is a system that offers at least two pulling speeds.
For residential or control wiring, consider the pullers’ rated at 1000 lbs. Many of these units allow you to attach a handheld drill that powers the pulling mechanism.
The key to a smooth cable feed is the proper alignment of the wire to its projected path. To best feed the cable, you should use sheaves to help direct the cable into position as it enters the conduit. Sheaves and rollers reduce the friction from pulling and lessen the strain on the wire.
When selecting a sheave be sure its maximum rated capacity meets or exceeds the cable puller's maximum pulling force.
For some types of wire conductor, you might want to provide more support. Conveyor sheaves are trays that have smaller sheaves that form a smooth, concave travel path.
And don’t forget to protect the wire as it enters the conduit opening. Nylon cable protectors should be placed in the end of conduit to shield the cable from sharp edges as it is being fed through.