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Can individual wires in multconductor cable be left exposed for 6" in a ceiling installation?

Can individual wires in multconductor cable be left exposed for 6" in a ceiling installation?

Can individual wires in multconductor cable be left exposed for 6" in a ceiling installation?

(OP)
Attached is a sketch which may better explain my question. We have some limit switches that will be located about 10' off the floor, and about 6" from the concrete ceiling. There are multiple switches to be fed by each run of cable.

We used armored cable from the control panel to near the switches. Can we just strip this armored cable back, leave the individual wires exposed for maximum 6". Or would we need a j-box, terminals, SO cord...that method?
I realize the second method would be the neater but it is also much more $$. Anything wrong Code wise on the the first method? I also don't like the idea of adding another terminal block into the circuit.

RE: Can individual wires in multconductor cable be left exposed for 6" in a ceiling installation?

Don't just strip the armor back. Do it the right way - get a junction box and wire it properly. Yeah, it's more expensive, but doing it right usually is. What do these limit switches do? What'll break if the wires to them are damaged? Can you justify saving a few $$ if the machine is damaged, or worse, someone gets hurt?


SceneryDriver

RE: Can individual wires in multconductor cable be left exposed for 6" in a ceiling installation?

Look in the code under open wiring. Then check the subsection on transition from enclosed to open wiring.
I haven't used that section for decades. I hope that it is still in the code.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Can individual wires in multconductor cable be left exposed for 6" in a ceiling installation?

Yes. Open wiring is still in the Canadian code. By our code you must use a junction box where the armored cable ends. From there, the rules for support and separation of open wiring may make it quicker and cheaper to use flexible conduit to connect to the switches.
Don't forget that your code may require the limit switches to be grounded.
You may have to use a small weather-head on the limit switch to comply with the rule that each conductor of open wiring must issue from a separate, bushed, hole.
Depends on your AHJ.
Yes, in Canada open wiring is still allowed, but the labor costs pushed it out of the market as an economical solution about 50 or 60 years ago.
Loomex/Romex took over the market very quickly.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Can individual wires in multconductor cable be left exposed for 6" in a ceiling installation?

(OP)
The below section does require a fitting to be used if I were to transition to what looks like an open wire on insulators - which is the only place I see open wiring mentioned in the Code.
So perhaps with a fitting my proposed install would be ok.
300.16 Raceway or Cable to Open or Concealed Wiring.
(A) Box, Conduit Body, or Fitting. A box, conduit body,
or terminal fitting having a separately bushed hole for each
conductor shall be used wherever a change is made from
conduit, electrical metallic tubing, electrical nonmetallic
tubing, nonmetallic-sheathed cable, Type AC cable, Type
MC cable, or mineral-insulated, metal-sheathed cable and
surface raceway wiring to open wiring or to concealed
knob-and-tube wiring. A fitting used for this purpose shall
contain no taps or splices and shall not be used at luminaire
outlets. A conduit body used for this purpose shall contain
no taps or splices, unless it complies with 314.16(C)(2).

But as my conscience got to me with the help of SceneryDriver's comment....I decided to put in a junction box. The Contractor and everyone else is happy. It will end up a lot easier to add anything in the future also. My biggest issue with that originally, in addition to the cost, was just all of the extra terminations that will be in the control circuit. I'm not crazy about that...but I can't allow myself to be worried it.




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