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Adhesive Cable Mounts for panels

2726 Views 42 Replies 19 Participants Last post by  GladMech
As Splatz said, "I'm a tool junkie".
So, I'm FINALLY working on panels, and am trying to up my game. Looking at Reddit's Cable **** sub, I'm wondering if adhesive cable mounts are a viable, code-worthy, option to help keep a panel nice, tidy & pretty. And, if y'all honestly believe it's a bad idea, what options are available other than shoving wires to the sides & into corners and making nice 90 degree bends?

What say you boys in the field?

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· Chief Flunky
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I still occasionally use waxed string, I have a few rolls left, more than I have time left to use. But usually for telecom. Have you seen the NASA PDF (attached)?
I use Kevlar lacing cord. Because it’s nearly unbreakable and “free” at the motor shop. Mostly to bundle cables in peckerheads. You can buy it cheap at EIS Sales. This is what it is used to control:


You lace up the turns and the internal wiring at the ends then everything gets coated in epoxy or varnish when used in a motor (dip and bake or VPI and bake).
 

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I'd like to see a photo of the Panduit method if you got one laying around in your phone

There are other manufacturers. Panduit is a trade name for most of us. Like we call side cutters Klein's.
 

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There are other manufacturers. Panduit is a trade name for most of us. Like we call side cutters Klein's.
Thx for the info, I've used this back in my low-volt days with Cat 3 & Cat 5e but never in a panel. Might try it
 

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Yea I've read the NASA manual. I really enjoy obscure stuff like that. There is a navy published one that covers the same stuff. The journeyman I work with was an electronics tech in the navy, worked on a lot of airplanes. It's fun when he opens a box and see the lacing, or spot tie as he calls it, that I've done. Normally leads to him telling the story of when they got new airplanes and he spent weeks cutting spot ties with a razor blade working on them to make them actually work.
 

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Thx for the info, I've used this back in my low-volt days with Cat 3 & Cat 5e but never in a panel. Might try it
Wiring duct makes panel building much easier. When using tyrap bases its a real pain to run all the wires perfectly to be tied down. In some instances bases work well for door operators. (push buttons and indicator lights).
Numbering being the most important thing. And building from a schematic.
 

· Chief Flunky
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Wiring duct makes panel building much easier. When using tyrap bases its a real pain to run all the wires perfectly to be tied down. In some instances bases work well for door operators. (push buttons and indicator lights).
Numbering being the most important thing. And building from a schematic.
Building from a wire list.

Field guys use schematics. Panel builders use wire lists. Many of them can’t read schematics.

It’s sort of like designers often just work off an IO list. The schematic is not used.

There are big advantages. UL requires you to lug the serial numbers of every part, even the wire. A wire list can have blanks for writing it down (tape worksheet in log book). If you have check off blanks you are less likely to miss a jumper. Panel building is very repetitive, both drawings and panels.
 

· Hackenschmidt
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So there's not code issues drilling screws/self-tappers into the side of panels?
A lot of the responses were for use in control panels. Control panel enclosures usually have what they call a subpanel, but not a subpanel in the usual sense, the subpanel is a sheet metal on standoffs off the back of the enclosure. The standoffs give you some space so you can screw things into the subpanel.

I don't think you'd get into a code debate with an inspector over zipping small self tapping screws from the inside out, but I couldn't guarantee it. I guess you could say that screw doesn't bond itself adequately so that could be an issue. Of course it could void a NEMA rating.
 

· Chief Flunky
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So there's not code issues drilling screws/self-tappers into the side of panels?
Most panels are not Listed. So the distribution panel in your house is almost always not Listed. Only the bus bar frames and the breakers are a Listed assembly, not the box it goes in. Boxes must meet NEC OR be Listed.
 

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Another option for electical panel fastening of wire clips, panel tags, and wiring duct is hammer drive rivets. They have a blunt end and will not harm wiring and are available in very short lengths.

Those cannot be removed. There has to be a way to replace devices. I like them tough. Easy and no tapping.
 

· Chief Flunky
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Those cannot be removed. There has to be a way to replace devices. I like them tough. Easy and no tapping.
We’ve debated this in house for a while. We sometimes deal with self contained panel mount style VFDs that weigh up to close to 500 pounds. A couple weeks ago we had a monster 700 HP, 407 pound VFD. It went into place nicely with a lift table. Then we get into supporting it.

Ultimate shear strength of a 1/4-28 Teks screw through 14 gauge sheet metal is 2350 pounds. Pullout is 1507 pounds. So with Teks they will pull out before they break iff..

Rivets can work but as stated it’s “permanent”. But there is an in between option, the rivet nut or rivnut. Mount like a normal rivet but remove the threaded insert then use like a threaded hole. Here are mechanical properties for Bollhiff brand:


Ultimate shear strength is 1100 pounds in steel. It is showing 1850 pounds shear strength. They have some special higher strength ones, too.

Finally for drilling and tapping bolts we have 1/4-20 is good for 1107 pounds shear in grade 5 or 1577 in grade 8.

Lesson learned: all 3 methods give fairly similar shear values for holding up a load, about 1100-1500 pounds shear strength, no safety margin included. So it comes down to which is safer, quicker, or cheaper.
 

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We use bunches of ty-rap bases. More on the outside of equipment than in panels. The panels will always have wire duct. I hate them because the screw is only 6-32 flat head. That's way too tiny for my taste - especially in steel sides of equipment. I have started using T&B TC503:
Rectangle Composite material Metal Auto part Engineering

Two 1/4-20 bolts! That's more to my liking, but then I do consider 1/4" plate sheet metal. :p
 

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what options are available other than shoving wires to the sides & into corners and making nice 90 degree bends?

What say you boys in the field?
I like them, but I use them sparingly and primarily for the keeping the feeders in the back of the gutters in panels. Sometimes for grounds too. Depends. I do like to use ty-wraps, however. Guys who are in service hate them, but I'm not in service, so I don't care. I like my work to look neat. I get paid to install and make it look as good as possible in a timely fashion. BTW, if you are into making your work look as good as possible you should look into joining the IBEW, which prides itself on craftsmanship. The apprenticeship hones your craft and focuses on making your work look good, at least in my local. They don't take kindly to slashers in the brotherhood.
 

· Chief Flunky
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All other stuff doesn’t involve adhesive. Wire duct is the most obvious. But you can screw straps (or tie wraps) down or use rivets. It all works pretty similar. If I spent the time and money on a CNC where I could just feed it a list of holes and let it do the work I might feel differently.

Take a look at this video:


This video shows drilling about 50 holes for a typical control panel that uses 100% wire duct and DIN rails. No tie wraps anywhere. Think for a minute how much time is involved doing this by hand. Tie wraps greatly reduce the hole drilling time when there are just a few wires. Wire duct makes a lot more sense when you have lots of terminals close together.

The truth is I don’t do it that way. It’s faster to just use self tapping screws. They are just as strong as drilling and tapping and I can do it all in one, once and done. If you use rivet nuts you only drill and the rivet eliminates tapping. I guess the ultimate speed would be a stud gun and nuts but I don’t know where to find stud guns that do #8-10 studs.
 

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A lot of the responses were for use in control panels. Control panel enclosures usually have what they call a subpanel, but not a subpanel in the usual sense, the subpanel is a sheet metal on standoffs off the back of the enclosure. The standoffs give you some space so you can screw things into the subpanel.

I don't think you'd get into a code debate with an inspector over zipping small self tapping screws from the inside out, but I couldn't guarantee it. I guess you could say that screw doesn't bond itself adequately so that could be an issue. Of course it could void a NEMA rating.
I always heard them called back planes
the panel has to have the standoff studs built in it for using those
 

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The truth is I don’t do it that way. It’s faster to just use self tapping screws. They are just as strong as drilling and tapping and I can do it all in one, once and done.
That's what I do as well, self-tapping wafers for duct and rail.


For other non-rail mount devices I will drill and tap, such as a control transformer.
 

· Chief Flunky
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· Hackenschmidt
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That's what I do as well, self-tapping wafers for duct and rail.


For other non-rail mount devices I will drill and tap, such as a control transformer.
I use 10-32 thread cutting hex-washer head screws (not to be confused with thread forming or self tapping). I get the correct sized drill bits in the stubby double-ended style, they work great and they're cheap in fiv-packs. This takes only a little more time than self tapping screws and you get a solid bond and full strength if you have to remove and replace things.
 

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we are not a panel shop but we do end up building a lot of panels. Licensed electricians are building these panels, so they arent cheap. Depending on whether we need to stretch it or not, sometimes we drill and tap for 8-32 or sometimes we just use self-driling/tapping screws

stickbacks are usually used on the doors, although recently, we tried heavy duty foam double sided tape and epoxy to glue panduit to the back on the door for the pilot devices.

a piece of equipment came in from europe on site that had these thin sheet metal standoffs that fit between the pilot devices and the locknut. They allowed panduit to be attached with screws or rivets without actually having to drill into the door. It was great, but when i looked into them, weeks lead time. None of this fancy stuff is stocked in North america whenever i look into it.
 
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