My project moving along...

[robh 12]

The building of the replacement to the ugly pics I posted before...

[BobLfoot 301]

Looking like it is coming along. There is a portion of NFPA 79 which refers to yellow wires being "ungrounded conductors who remain energized when the main disconnect is in the off position". Most OEM's I've worked with interprted this to mean that panel to panel wires were yellow. Just food for thought. Then I've also seen yellow used for 24 positive VDC wiring opposite blue 24 VDc negative wiring.

[TimWilborne 108]

I concur with what Bob said. Yellow wires are usually panel to panel wiring or an external power source that isn't removed by the normal disconnect And the panel does look very nice

[Ken Moore 23]

I have one PLC-5 panel that was built in the mid-90's that uses yellow for all the 120VAC I/O wiring. This PLC does not have any low voltage discrete I/O. I wasn't involved in the installation, and when I asked about the yellow wiring later, the explanation given was " our maint. guys aren't familiar with 120VAC inputs, so we used yellow to get their attention". I too, am used to yellow being externally powered, but as noted above, I've seen other uses also.

[Clay B. 1]

From a time log ago. I used to see yellow in machines runing on relay logic prior to having a PLC. The way it was explained to me was that it told you that the yellow ment it was 120 VAC control versus 120 power. Usually each were a seperate circuit. Now that I have told I have been doing this way to long..... Pannel looks good. Just curious about using 2 PIC boxes (That is what they look like to me anyway.

[robh 12]

Years back here, yellow was determined to be 110vac inputs to a plc and purple was for 110vac outputs. This had come from other places in the plant where white had been used as a "hot" wire and mass confusion over colors. I hate to say it, but it may not be "perfect" but its sure a heck of a lot better than it was. Always moving forward. They are NET-AIC modules. The one on the left is just in there to take up space until my Net-ENI gets here. The one on the right will connect to com 0 on the 1500 and to a DH-485 PanelView 1000 color touch. When the Net-ENI gets here it will be connected to com 1 on the 1500 and used to possibly send data over ethernet to LabView, at least thats the theory anyway.

[ssommers 20]

This reminds me of a certain completely color-blind electrician I had once upon a time at another company... He used yellow & purple for 110 VAC circuits because they were high contrast colors. It drove me BONKERS the first time I went into a panel he wired! Then there was yet another company where they were mass producing machines going worldwide and purple was used as the "debug" wire color, so it could be ANY voltage. If a wire was purple, a wiring mistake had been found & corrected by a technician during testing and the assembly people would send the original wiring person over to correct their own mistakes before shipping it out. Then there's the place I work now... 480 VAC is orange, brown, & purple so they can tell the phases apart. UGH!!! The real key to color coding is to make sure that everyone knows what the color codes mean. And there MUST be a color set aside for ungrounded mixed voltage sources. Almost every machine I have has at least start relay circuit from the machine before it and I'd really like to know what will still be hot after turning off the disconnect. If I could start all over again with a fresh plant & panel, I'd prefer to keep it simple & follow NFPA 79's color codes. Edited 10 Apr 2008 by ssommers

[Atlascycle 0]

That panel is looking good Keep us Posted on your progress. Jason

[BITS N BYTES 66]

Looks like you have chosen NOT to build your panel to any recognized standard. That's fine if your will customer accept it. If you want to use a recognized standard in the USA then I would recommend using NFPA79 Electrical Standard for Industrial Machinery. In reference to the wire color discussed in this thread. NFPA 79 Section 14.2 Identification of Conductors states:- 14.2.4.1 Ungrounded circuit conductors that remain energized when the supply disconnecting means is in the off position shall be consistently applied as either ORANGE or YELLOW. These color identifications shall be strictly reserved for this application only.

[BobLfoot 301]

THis was true in the 2002 Edition of NFPA 79 but removed from the 2007 Edition. An ammendment is pending consideration to re-instate it. Comment cycle ends 5/2/2008.

[robh 12]

This panel is for an in house project. WE are the customer. This is in a manufacturing facility. As far as recognized standards go...I agree with what ssommers said, "If I could start all over again with a fresh plant & panel, I'd prefer to keep it simple & follow NFPA 79's color codes." But in the world I live in this just isn't practical. We have an exceptional compliance record with OSHA and our AHJ and work closely with both.

[BITS N BYTES 66]

Thanks for the correction! I've had the 2007 Edition for some time but failed to notice this change. While reviewing changes in Edition 2007 I only goat as far as page 4 before falling asleep.

[TConnolly 13]

Looks nice Rob. Really! I'm surprised. Its such a gripping read full of suspense and excitement. For reference, I attached the relevant sheet from the 2007 NFAP79. FWIW, its section 13.2, not 14.2. Section 13.2.4 addresses the yellow/orange issue. It states that Orange is "strictly reserved for this application only." It says nothing about yellow wires. I do not know why yellow was removed from the designation, but if I were to offer a theory II would guess it may have something to do with the use of green with yelllow stripe or yellow with a green stripe to designate ground wires under the IEC - but that may be completely wrong. 2007_NFPA79_13_2.pdf Edited 10 Apr 2008 by Alaric

[robh 12]

I dug through the UL 508A Standards for Industrial Control Panels and it too states in 66.9.1 d "Yellow- ungrounded control circuits or other wiring, such as for cabinet lighting, that remain energized when the main disconnect is in the "off" position". After talking about this with my cronies here at work we have decided to stay with our current color scheme. Mostly because that's how other things here are and everybody understands it I guess. Thanks for the compliments and criticism, hopefully it will improve what I am doing. Will post more as I can. Rob