Yellow for external power, but....

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JAZZNSKA

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Hello all.

I understand the idea of the color of any conductors that bring power into a panel from a different panel need to be yellow, (as they won't be de-energized by the local disconnect) but I have a question about implementation...

Say I have a panel, and the coil of one relay in my panel is powered by an external source. (so that I know when a piece of equipment in another panel is running) The two wires that power the coil of this relay need to be yellow in this panel. I intend to bring this signal in using a multiconductor cable between the two panels. Do I need to purchase a cable with yellow conductors? or can I use an off the shelf cable, then terminate the wires and run yellow from the terminations to the coil?

Thanks for the help.
 
Yellow insulation identifying a 'foreign' voltage is not a requirement, however it is recommended in NFPA79 and it is a common practice.

I have seen, built, and designed many panels where the field wiring is standard colors and the interior wiring uses yellow after the terminal blocks.
 
good question.

the yellow wire thing comes from nfpa79 and not the nec.

I am not real sure that nfpa79 calls out the color of wiring between two different control panels.

IIRC, NFPA79 has some color code exemptions for MC acbles anyway. You might want to take a look.
 
If you used yellow wire in between the cabinets it would only be correct on one end.

I agree with using yellow wire internal to terminal blocks and standard colors for the interconnect wiring.
 
jim dungar said:
Yellow insulation identifying a 'foreign' voltage is not a requirement, however it is recommended in NFPA79 and it is a common practice.

I have seen, built, and designed many panels where the field wiring is standard colors and the interior wiring uses yellow after the terminal blocks.
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Jim,
NFPA79 is either non-adopted by a company and therefore does not apply at all; or it is adopted and is therefore legally enforced by OSHA because your company signed on to it. There is no "recommended" involved.

If you are an industrial site in the US then your company should adopt NFPA79. At that time it becomes a legal requirement per OSHA.

NFPA79:2007 13.2.4.1
The color ORANGE shall be used to identify ungrounded conductors that remain energized when the main supply circuit disconnecting means is in the off position. This color identification shall be strictly reserved for this application only.
Exception No. 2: Where the insulation used is not available in the colors required (e.g., high temperature insulation, chemically resistant insulation).

Since you are using multiconductor cable:
Gather all the terminal blocks in the panel that have conductors that may remain energized into one location. Use ORANGE terminal blocks or other permanent ORANGE marking on the blocks. Land your cable on these blocks. Use ORANGE from the blocks to the relay coil.
 
pfalcon said:
If you are an industrial site in the US then your company should adopt NFPA79. At that time it becomes a legal requirement per OSHA.
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Not so. If your company adopts it as a company standard, that what it is; a company standard. For instance, your company could make it a company standard that everyone wears eye protection 100% of the time, even in enclosed offices with no eye hazard. That does not make it an OSHA requirement. Your company could discipline you for not complying, but OSHA couldn't cite them if you didn't comply.
 
pfalcon said:
Jim,
NFPA79:2007 13.2.4.1
The color ORANGE shall be used to identify ungrounded conductors that remain energized when the main supply circuit disconnecting means is in the off position. This color identification shall be strictly reserved for this application only.
Click to expand...

When did this change? the 2002 code says yellow or orange. (14.2.4.1)

My copy of UL508a says yellow or orange. My copy is dated Dec 2007.

UL and NFPA have been pretty good about harmonzing their standards.
 
petersonra said:
When did this change? the 2002 code says yellow or orange. (14.2.4.1)

My copy of UL508a says yellow or orange. My copy is dated Dec 2007.

UL and NFPA have been pretty good about harmonzing their standards.
Click to expand...

NFPA79:2007 13.2.4.1
2002 was the prior cycle.

The effective date for the 2007 edition of NFPA79 is August 17, 2006.
NFPA seems to make standards effective in August prior to the year on the cover.
 
G0049 said:
Not so. If your company adopts it as a company standard, that what it is; a company standard. For instance, your company could make it a company standard that everyone wears eye protection 100% of the time, even in enclosed offices with no eye hazard. That does not make it an OSHA requirement. Your company could discipline you for not complying, but OSHA couldn't cite them if you didn't comply.
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I see you haven't dealt with regulatory agencies much. Per the OSHA mandate, which is in the act itself, they must recognize "National Consensus Standards" and hold all parties to them. OSHA must file an appeal if they feel their standards are superior. Therefore if your company adopts a "National Consensus Standard" such as NFPA79 then OSHA must hold you to that standard unless they file an appeal.

By the way, last time I checked the OSHA requirement is that each industrial plant must determine the level of eye protection required at their site. In your example 100% does become the OSHA requirement and OSHA can cite/fine/jail them for non-compliance. I specifically looked up eye protection when our company adopted side-shields.
 
I send Ul an email and asked them.

I had understood UL was making an effort to harmonize their standards for industrial control panels (508a) with NFPA79 and NFPA79.

I noticed this a few years ago when UL changed their ampacity charts to match the NEC ampacity.

recently, it has come to my attention that the 2007 edition of NSPA79 now requires externally powered conductors (those not disconnected by the panel disconnecting mechanism) to be orange in color. The previous edition allowed orange or yellow.

The latest version of UL508a (Dec 2007) allows such conductors to be either yellow or orange.

Is there any intend to change UL508a to conform to with NFPA79?

This could become an issue with people who have adopted NFPA79 as a safety standard under OSHA regulations, as a UL listed control panel might not be in compliance.
Click to expand...
 
petersonra said:
I send Ul an email and asked them.
Click to expand...

Good idea. Comments from the NFPA79:2007 introduction include:
... effort in harmonizing an existing NFPA [79:2002] standard with an existing IEC standard [60204-1].
... chapter numbers to align with IEC 60204-1.

So we can see from this where NFPA is going with their stuff.
 
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