Cable Glands on a UL508a Panel

doomed9

Member
Location
Hopkinton, MA
Occupation
Control Systems Designer
I need to install 4 cable glands on a UL508a panel while maintaining a type 4x environmental rating. Does a 4x enclosure only maintain it's environmental rating when a type 4x cable gland is installed AND a cable of the correct diameter is run through it? Or can I install the cable gland without the cable through it and still label my enclosure type 4x? If it helps, for this example I am looking to use LTCG M20 from Heyco.
 
In addition to not maintaining the NEMA rating, without a cable you also have a shock hazard since you will basically have a 1/2" hole in the side of the panel.

Once I had a gland plate that I wanted to include a provision for adding an additional cable through in the future. The issue was because KOs were very close together, it would pretty much be impossible to install an additional cable gland with the others already installed. To avoid having to take out all the other cables and rewire everything in the future, I installed the spare cable gland from the start. To overcome the problem of the empty hole, I cut a short piece of round PVC rod that was a suitable diameter, then put it in the cable gland and tightened it down.
 
In addition to not maintaining the NEMA rating, without a cable you also have a shock hazard since you will basically have a 1/2" hole in the side of the panel.

Once I had a gland plate that I wanted to include a provision for adding an additional cable through in the future. The issue was because KOs were very close together, it would pretty much be impossible to install an additional cable gland with the others already installed. To avoid having to take out all the other cables and rewire everything in the future, I installed the spare cable gland from the start. To overcome the problem of the empty hole, I cut a short piece of round PVC rod that was a suitable diameter, then put it in the cable gland and tightened it down.
As long as I put in a "filler" cable of the correct diameter there is no issues?
 
What I did when I was building panels, was to punch out the hole for the CGB (cable gland), then close it with a listed Type 4 hole seal, and provide the CGBs in a bag taped to the inside of the door. That way the installer is responsible for that CGB, but my panel, as shipped, was legitimately Type 4. That way if they decided to use conduit and Myers hubs instead, no big deal.

But honestly, I now wish I had thought of just plugging the CGB…
 
What I did when I was building panels, was to punch out the hole for the CGB (cable gland), then close it with a listed Type 4 hole seal, and provide the CGBs in a bag taped to the inside of the door. That way the installer is responsible for that CGB, but my panel, as shipped, was legitimately Type 4. That way if they decided to use conduit and Myers hubs instead, no big deal.

But honestly, I now wish I had thought of just plugging the CGB…
What section of UL508a tells you that cable glands must be plugged with a wire in order to receive their environmental rating? Or does this have to do with the way the cable glands are investigated?
 
As long as I put in a "filler" cable of the correct diameter there is no issues?
I didn't use a piece of cable for two reasons:
1) Water may ingress by travelling though the inside of the cable. There is nothing to seal the area between the cable conductors and the cable's outer insulation.
2) There would be the cut end of the cable exposed on the outside, which not only looks not the best, but should the other end of the cable on the inside somehow become energized you then have a problem. (I guess to solve this shock issue you could ground every conductor of the cable on the inside.)

Perhaps if you have an even number of cable glands that need to be plugged you could use a single piece of cable for every two glands, just making a loop of cable between the two. That overcomes both of the issues above.
 
Top