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Posted By: meisgq Tray Cable - 02/15/13 05:28 AM
Hello,
I may have to use tray cable for a camera being installed on a light pole. I can't run another conduit so we may have to share the power conduit. I don't think RG59 tray cable exists. UTP tray cable with baluns? Any suggestions?

Thanks in advance.
Posted By: jwooten Re: Tray Cable - 02/15/13 01:12 PM
Fiber...
Posted By: Silversam Re: Tray Cable - 02/15/13 02:29 PM
The NEC says that signal cable can share a raceway with power - AS LONG AS THE INSULATION ON THE SIGNAL CABLE IS THE SAME AS THAT OF THE POWER CABLE.

Fiber, of course, as Jim said, not being electrical does not fall under the same requirements.

Sam
Posted By: Arthur P. Bloom Re: Tray Cable - 02/16/13 02:43 AM
Wireless camera
Posted By: hbiss Re: Tray Cable - 02/16/13 02:56 AM
Originally Posted by Silversam
The NEC says that signal cable can share a raceway with power - AS LONG AS THE INSULATION ON THE SIGNAL CABLE IS THE SAME AS THAT OF THE POWER CABLE.

No Sam, in this case that's not true and it really applies in only a few cases. I get this exact queston all the time though sometimes it's speakers instead of cameras.

The "reclassified" wiring or cable has to be functionally necessary for the operation of whatever the line voltage conductors power that it is run with. An example of that would be LV control wiring going to an A/C unit. You are allowed to reclassify a CL2 circuit to Class 1 and use TFFN or THHN for the LV within the wiring box on the unit- which also contains the line voltage to power it.

No way is a camera necessary for the operation of the lamps on a light pole.

The only way to comply with the code is to enclose the power conductors in conduit or sealtite within the light pole. This would require suitable connectors and wiring boxes at the top and bottom that encloses the conductors. Once you do this the pole becomes a chase and you can run CL2 or CM cable within the pole.

Using tray cable is not the answer.

Fiber often is the only alternative.

-Hal







Posted By: Silversam Re: Tray Cable - 02/17/13 12:38 AM
Interesting, Hal. I used to have this problem with elevator phones. I would jphave to bring dial tone into the "chase" that fed the elevator control equipment to get to the terminals for the traveller cable.

All the wiring in the chase was 120VAC or higher. I couldn't run quad through the chase and be compliant, so at the nearest box I would change over to AWG14THHN (or whatever- early on it was TW).

I looked over the current code and you are on the money. I don't know if anything has changed recently ( the last 30 years) or not; but you're absolutely right. It's run seal tight to a box or fiber.

Thanks for setting me straight.


Sam
Posted By: hbiss Re: Tray Cable - 02/17/13 02:32 AM
Thing is if you run fiber you are still faced with how do you power the camera. You can run 120v up the light pole no problem and put a transformer or power supply in the housing with the camera I guess.

-Hal
Posted By: meisgq Re: Tray Cable - 02/17/13 05:56 AM
I appreciate the input. We're weighing all options. Just to clarify, even if the insulation on both cables is rated for 600V, we're still not allowed to run signal and power in the same raceway? It looks like fiber or wireless at the moment.

Just for fun... Let's say the power cable is there for the camera. In that case, can we reclassify the signal cable because it is functionally necessary for the camera operation?
Posted By: hbiss Re: Tray Cable - 02/17/13 05:43 PM
Quote
Just to clarify, even if the insulation on both cables is rated for 600V, we're still not allowed to run signal and power in the same raceway?

No.

Quote
Just for fun... Let's say the power cable is there for the camera. In that case, can we reclassify the signal cable because it is functionally necessary for the camera operation?

Only if they are the only line voltage conductors in the pole. I actually heard someone mention that somebody does make a 600v listed CAT5 cable for industrial control situations where it would terminate in the same cabinet with line voltage. Good if you can find it. There is no 600v listed coax though.

-Hal
Posted By: Arthur P. Bloom Re: Tray Cable - 02/17/13 06:59 PM
Use a 12-volt led for the lamp.

or

Send 40 Vac up the post and use a 1:3 transformer at the top for the lamp.
Posted By: hbiss Re: Tray Cable - 02/17/13 10:12 PM
Originally Posted by Arthur P. Bloom
Use a 12-volt led for the lamp.

or

Send 40 Vac up the post and use a 1:3 transformer at the top for the lamp.

I'm assuming that this is an existing light pole.

-Hal
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