Ask any industrial contractor, and they’ll tell you that workplace safety is always a primary concern. That’s why properly grounding electrical equipment is so essential — it can prevent serious injuries or even fatalities, not to mention potential damage to equipment or property.
Excess electrical charges can be caused by power surges, equipment malfunction, and even lightning strikes. Grounding wires connect equipment to the earth. Electricity takes the path of least resistance. In the event of a short circuit or power surge, the excess electricity safely travels through the ground wire to the earth, rather than through equipment (or people!) that may be nearby. In this way, grounding helps prevent serious injuries, equipment damage, and potential fires.
Several grounding systems are commonly used in industrial applications, depending on the power source (e.g., utility service, generator, or transformer) and the equipment used. All, however, use grounding wire in some form.
Grounding wire is almost always made from copper and is available from most copper wire manufacturers in several gauges. Insulated versions typically come with either polyvinylchloride (PVC) or high molecular weight polyethylene (HMWPE) insulations in green, green/yellow, or black.
While each has benefits, it’s important to note that both bare and insulated versions perform the identical grounding function.
Insulated grounding wire offers several practical advantages over its bare counterpart, including:
Labeling and identification. Insulated grounding wire is available in several colors, and some copper wire manufacturers like Kris-Tech offer custom colors, striping, and even jacket printing. Color-coding and labeling can simplify wire identification and the termination process, reducing labor costs and time on the job.
Use in conduits. Grounding wire is often pulled through conduits, and insulated wire offers an advantage here as well. The ‘slippery’ nature of the insulation makes pulling the wire through conduits much easier, especially if there are turns or bends in the pipe.
Open busbar environments. A busbar is a metal bar or strip used for high current power distribution inside switchgear and panel boards. Busbars are typically uninsulated, so insulated grounding wire is used to prevent unintended contact between the grounding wire and the busbar.
Theft protection. Copper wire theft is a common and costly crime. In 2019, the Missouri Department of Transportation reported spending almost $1 million annually on repairing street lights caused by copper wire theft. Insulated copper grounding wire is more difficult for thieves to ‘process’ and much less attractive theft target.
Bare copper grounding wire is less expensive than insulated grounding wire and works well in many industrial applications. Particularly for large projects, using bare copper may yield significant cost savings.
In some cases, bare grounding wire may also be less labor-intensive, as it doesn’t need to be stripped before termination.
How best to choose the right grounding wire (bare versus insulated) for your application? In most cases, either will perform the technical grounding function. The first step, however, should be consulting your local codebook. Often, local building codes may definitively dictate which grounding wire to employ.
Sometimes, however, the code can be ambiguous. In these cases, it’s always best to work with local inspectors or officials to help interpret the code and confirm which type of grounding wire to use for your application. Securing this confirmation before installation will ensure an official sign-off and eliminate the possibility of a ‘rip and replace.’
Kris-Tech offers many different bare and insulated (PE/PVC) grounding wire options in a range of gauges. We manufacture our UL-certified grounding wire in two specific colors, green and tan, and also offer a black, non-UL version that is identical except for the insulation color.
Kris-Tech also provides custom striping and printing options to help simplify and speed the wire termination process.
As with all of our wire products, Kris-Tech can provide non-standard lengths, several packaging and labeling options, and never levies cut or reel charges.