Mechanical protection of the emergency system

[RUWired]

In article 517.30(c)3 exception #5, is mc cable a listed "cable assembly" used for flexible wiring to a removable lay-in troffer? 330.2 describes mc cable as a factory assembly.These lights would be located in one of many o.r. rooms on the emergency system.The entire emergency lighting system is in emt up to the point of transistion to these lights.
Rick

 

[bdarnell]

Re: Mechanical protection of the emergency system

Excerpt from 2002:
Exception No. 5: Flexible metal raceways and cable assemblies shall be permitted to be used in listed prefabricated medical headwalls, listed office furnishings, or where necessary for flexible connection to equipment.

Handbook explanation:
Exception No. 5 recognizes that flexible connections are sometimes required for equipment and, for practical reasons, permits their limited use.

It does say equipment, not fixtures.

 

[roger]

Re: Mechanical protection of the emergency system

You would have to use HCFC for both the Normal and Critical Branches, common interlocking MC can not be used in Patient Care Areas, see 517.13(A), 517.13(B) and Ex.#2.

Whether a flexible connection can be used for this under 517.30(3) is another issue but EX # 5 would not help.

Roger

[ February 06, 2006, 06:32 PM: Message edited by: roger ]

 

[RUWired]

Re: Mechanical protection of the emergency system

article 100 definitions lists luminiares (fixtures)in the description of "equipment",so greenfield should be allowed.I guess i need to know if hospital grade mc is allowed as well.I'm stuck on the "cable assembly" part and if the lahj will allow it.
Rick

 

[roger]

Re: Mechanical protection of the emergency system

Greenfield can only be used if it complies with 250.118(5) & (6), as far as Hospital Grade MC, you are probably talking about the green HCFC, which is actually a type of AC, not MC.

Now, Exception #5 to 517.30(C)(3), in most situations it is not really necessary to use a flexible connection for a luminaire, so depending on the inspector and AHJ, you may be out of luck.

BTW, I am on your side though.

Roger