On the back page of Dec's issue of EC&M is an ad for this product, stating that it has the capacity for "28 12-gauge power cables".
It's a raceway for workstations, made of "LIGHTWEIGHT, easy-to-handle, scratch-concealing plastic". Barriers separate the V/D/V wiring from the power.
Let's see, now. Derated to 45% for the number of conductors.........What do you think??
I speld bad so itz eddditd



[This message has been edited by electure (edited 01-16-2002).]

uhhh,.... one every 25" ?

The point I saw was that even a 90° #12 conductor would be good for only 13.5 amps, and there isn't a way to limit the current to that.
(I can see plenty of IT and plant maintenance types thinking of stuffing 7-4 wire circuits through this stuff and putting them on 20 amp breakers)....as the ad might lead them to believe

I thought in 4 wire circuits, only 2 were current carrying. That would mean 7-4 wire circuits would have 14 current carrying conductors and be derated by 50%. That means a #12 THHN should be able to handle 15 amps. I would think using fewer #10 THHN circuits at 20 amps would be more appropriate.

Scott,
it's not quite the same as bundeling like numbers of #12 thhn together, the sheathing maintains seperation...

I need to apologize for not explaining the product properly. It's like a plugmold.
Here: www.panduitncg.com/whatsnew/TG_news_release.asp
The ad shows 15 #12 THHN in the top section. "cables" was in a quote from them.
By 4 wire circuits, I meant 3Ø, 3 hots, one neut 120 v circuits (probably nonlinear to boot) All conductors are current carrying conductors.
What kind of 4 wire circuit has only 2 current carrying conductors??

oh...ah...well that's surface raceway...

Sorry, I assumed this was for office workstations using single phase. The four wires would then be 2 hots, a neutral and a ground. In that case only the two hots count as current carrying conductors.

Scott, take a look at 352-4. Does it apply to the system your talking about?

Nick, this stuff is plastic, and 352-4 applies to metal raceways.
(and Ross, I did forget to include a grounding conductor in my count)

Scott,

I could easilly see where you were going with this.
Sounds like you have been involved with Vendor coordinated project surveys too! That's where I heard a few really good ones about power circuits, from the IT rep's of the Vendors.

It would take Eons to explain the maximum derated capacity of 45% to them, if the case was to run 7 - full boats [4 wire circuits].

The first thing they would say is:
"Derated Ampacity? What Planet are YOU from?"

Then the impossible task of explaining that there are 28 load [current] carrying conductors and only one non-load carrying conductor [the Equipment Ground Bonding Conductor], which will always bring up the 'ol:
"But the ""Neutral"" doesn't carry any load" debate.

I would like to hunt the joker down that started this viscious rumor and send that clown back to his / her planet of origin - or at least somewhere in deep space!

Never really installed too much of that Panduit stuff. Cable guys love it, and I guess for Voice and Data cabling it would be better than fishing down an Insulated wall [or a wall with Asbestos Impregnated Plaster / Gypsum board].

Scott SET.

The other thing about this type of product is the plastic divider between the power and communications sections. How does this provide any shielding? When installing Cat-5 cable in the open above ceilings, we are told that the Cat-5 must be kept at least 6" away from power conductors in metal raceways and 12" from power cables without metallic jackets and 12" from fluorescent light fixtures. We are told that this separation is to avoid interference with the data transmission. In both cases I would think that the metal conduits and metal fixture would be a much better shield then the plastic divider. Why is separation required from metallic raceways, yet this little piece of plastic is ok in the wire way?
Don(resqcapt19)

Don, you bring up an excellent point!
For that matter, Office Furniture presents very much the same situation. The power conductors are not shielded, but in a nonmetallic jacketed cable, and the Cat5 wiring is often run right through the same chase. EMI should run rampant.
(Maybe this raceway would cut down on the number of personal-use heaters one finds so often in offices, I should think it would generate plenty of heat)

So, do you believe that this product can be applied as advertised? I sure don't.

The add just says that you can install the power cables, it doesn't say that you can use them.
Don(resqcapt19)