Tray cable is a unique and multi-faceted product used across many control and power applications, including in facilities like chemical and industrial plants, utility substations, and commercial and retail buildings.
According to the National Electrical Code (NEC), tray cable is described as: “a factory assembly of two or more insulated conductors, with or without associated bare or covered grounding conductors under a nonmetallic sheath, for installation in cable trays, in raceways, or where supported by a messenger wire.”
The NEC casts a pretty wide net over its description, but for a good reason. Like any other wire sold, tray cable comes in different forms to fit unique applications.
So, before placing an order, think about how the tray cable will be used, where it will be installed, and what conditions it will likely experience during its usable life. Knowing what you want ahead of time will limit mistakes, cut down on costly delays spent tracking down answers, and get you the cable you want when you want it.
There are seven questions you should be able to answer before placing a tray cable order with your electrical distributor. Forgetting to answer even one of these questions could leave you scrambling with a bunch of wire you don’t want or need.
This one seems like a slam dunk, but having a good handle on how much tray cable you need can help you avoid the agony of either ordering way too much product or not enough.
Concerned the amount you need won’t meet minimum order requirements? Kris-Tech has a low minimum order threshold, making even small tray cable orders possible.
What size wire do you need to safely allow current to flow?
The larger the wire, the higher the carrying capacity will be. But what are the consequences of misjudging the wire size in the first place? Sometimes, it can be the difference between a safe installation that lasts for years and a possible electrical fire.
Tray cable is available in a wide range of sizes, from #18 AWG into MCM sizing. If the gauge is too small for the current pushed through it, heat buildup can melt the insulation and expose the copper conductors to the elements. Once exposed, those conductors could short and start a fire.
But what happens if the cable gauge is bigger than what the project needs? For starters, you’ll be wasting money on an over-spec’d cable that was too big for the job in the first place. You may also have to pay higher costs for larger conduits to fit the larger gauge tray cable if it isn’t exposed run (-ER) rated.
How many conductors (wires) do you need inside the tray cable?
The answer to this question is entirely dependent on the job itself. Depending on the application, you could need as few as two conductors, though there are plenty of cases where you could need a multi-conductor cable.
Tray cable insulation comes in several forms, so it’s good to know what type you need for the job.
VNTC tray cable uses THHN insulation around the individual conductors. This insulation gives the conductors flame retardant properties and protection from the elements.
XPTC tray cable, on the other hand, uses cross-linked polyethylene (XLPE) to insulate the individual conductors. Compared to THHN, this insulation gives the conductors higher heat resistance and is easier to maneuver inside conduit or along raceways. XLPE insulation is durable and versatile, making it optimal for installations in wet or dry locations, indoors or outside, and in tight spaces.
Tray cable shields wrap around the conductors to protect them from outside interference. A shielded tray cable can also protect sensitive equipment from electromagnetic energy coming from the tray cable itself.
Kris-Tech’s tray cable can be ordered with an aluminum-Mylar shield with a tinned copper drain wire for additional protection.
Jacketing provides overall protection to the tray cable conductors, allowing them to withstand damage more effectively.
Kris-Tech’s tray cable is jacketed using polyvinyl chloride (PVC), which is one of the most used jacketing materials. PVC is heat, oil, chemical, and sunlight resistant. It can also protect control cables from abrasion damage.
Other jacket types include thermoplastics, thermosets, and low-smoke, zero-halogen options. You can learn more about each type of jacket by reading our tray cable jacket guide.
A crucial aspect that sometimes gets overlooked is what tray cable color code will be needed for the project.
There are three commonly used color codes; E-1, E-2, and M-4, though custom colors and prints are available.
E-1: This color code has white and green conductors included alongside black, red, orange, and blue.
E-2: There are no white and green conductors in this tray cable color group. Instead, the colors are black, red, blue, orange, yellow, and brown.
M-4: For those who like their tray cable a little more monotone, M-4 color-coded tray cable uses all black conductors with printed numbers on the insulation.
Unicorn: This Kris-Tech concoction is available as a build-your-own option, allowing customers to select the colors and prints they need for the job.
Once you know what length, gauge, conductor count, insulation, shielding, jacketing, and colors you need, ordering your tray cable should be effortless.
Quickly get what you need without the risk of ordering too much, too little, or missing a piece of the puzzle that could potentially haunt you later.
As always, if you have questions, Kris-Tech is here to help. Our dedicated tray cable experts can guide you through the purchasing process and help you complete your project safely.