Cables in Above Ceiling Space

[dasarmin]

Does the NEC address how long a CMP or CMR cable run can be outside of a raceway (conduit)? Our IT group has ask me about an installation pending where communication / network cables will be run in the above ceiling space for up to 200?. I don?t have the details (I?ve ask) of what this above ceiling will be like, but it should be our standard (non plenum) space. All our HVAC is in ducts so the above ceiling is not used for any air handling, all lighting is standard fluorescent wired with MC cable.

Even though the space, as I understand it, is non-plenum we?ll probably run plenum rated cables CMP or CMR. Since this work will take place in existing occupied office space, not having to install conduit would an advantage.

If this allowed (cable outside conduit), does NEC specify how this cable should be secured?

 

[petersonra]

as long as it is not laying on top of the drop ceiling, cable distance is solely about how long that kind of commcable can be run before the signal degrades too much.

I suspect the manufacturer will have some sugegstions about how often the cable needs to be supported. IIRC, it is not real close. Most people seem to tie wrap it off a lot closer together than is actually required so it looks better.

 

[north star]

= = = >
dasarmin,

This very topic was discussed recently on this Forum,
...in the Low Voltage and Limited Energy Thread.

See this link:
http://forums.mikeholt.com/showthread.php?t=147272

FWIW, ...raceways are not required!......Hope this helps!
< = = =

 

[btharmy]

One thing to keep in mind above a ceiling is the rating of the cable jacket. If it is in a raceway then it won't matter. However, if it is a plenum ceiling, make sure to use plenum rated cable if not in a raceway.