fiber optic cable in tray with MC cable.

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lostinafrica

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I am working a job were metal clad fiber optic cable 770.4 (B), is being installed in the same tray as MC power cable. This seems to be a violation of 770.52. The contractor insists by the definition of Raceway 100-I that MC is considered a raceway and both cables MC power and metal clad fiber optic can be in the same tray. Does anyone know if this is acceptable? Please make specific reference to code, UL, FM or whatever you are basing your interpretation on
 
Re: fiber optic cable in tray with MC cable.

770.133 Installation of Optical Fibers and Electrical Conductors
(A) ... Nonconductive optical fiber cables shall be permitted to occupy the same cable tray or raceway with conductors for electric light, power, Class 1, non?power-limited fire alarm, Type ITC, or medium power network-powered broadband communications circuits, operating at 600 volts or less. Conductive optical fiber cables shall not be permitted to occupy the same cable tray or raceway with conductors for electric light, power, Class 1, non?power-limited fire alarm, Type ITC, or medium power network-powered broadband communications circuits.
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The installation would be a violation of the above 2005 code section, however I do not understand the reason for the rule. I see no more hazard with the MC fiber cable in the tray, then I see for an additional MC power cable in the same tray.
Don
 
Re: fiber optic cable in tray with MC cable.

MC cable is not a raceway it's a cable assembly. MC cable is not a conductor it's a cable. MC power cables and MC fiber optic cables can be in the same cable tray. The restriction is for power conductors and fiber optic cables in the same cable tray, not power cables.
 
Re: fiber optic cable in tray with MC cable.

It seems odd that 770..12(A) and 770.133(A)allow fiber within electrical raceways when 330.8 won't allow anything other than electrical service in the same raceway.
Rick
 
Re: fiber optic cable in tray with MC cable.

This is one of the few times I have to disagree with Don. The fiber optic cables are sharing the cable tray with a Chapter 3 wiring method, not with conductors.


It seems odd that 770..12(A) and 770.133(A)allow fiber within electrical raceways when 330.8 won't allow anything other than electrical service in the same raceway.
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And again, it uses the term conductors. We aren't talking about conductors, we are talking about MC cable.
 
Re: fiber optic cable in tray with MC cable.

770.52 states "...not be permitted to occupy the same calbe tray or raceway wiht conductors for electric light, power,...".

Yes it says conductors not calbes, but 330.2 states "Metal Clad Cable, Type MC. A factory assembly of one or more insulated circuit conductors....". Reads like MC cable is a "Factory assembly" and also conductor.

If this is true, and NEC 2002 states it is, than conductive FO cable can't be installed in tray with power or class 1 circuits to mention just a few.
 
Re: fiber optic cable in tray with MC cable.

Steve,
You make a good point. I think that I just read over the word "conductors".
Don
 
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