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Thread: Color coding fiasco
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04-06-2016, 01:36 PM #1
Color coding fiasco
Saw this panel at a motel. All circuit breakers were for new HVAC units at the rooms.
Lots of 'white' ungrounded conductors; and, a bunch of 'blue' and 'green' grounded conductors. Should they re-wire, or just re-color the existing? Any thoughts?
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04-06-2016, 03:14 PM #2
Re: Color coding fiasco
The color coding is an issue, yes, but the number of conductors in those conduits creates a derating issue (extrapolating what is shown in the photo outward as being the same for a combined length of bundling/lack of maintaining spacing/more than three conductors in a raceway/etc for greater than 24 inches).
While they are re-routing those conductors for the derating issue, they might as well replace the wiring with conductors of the proper colors as that is also a requirement.
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04-06-2016, 04:25 PM #3
Re: Color coding fiasco
Since conduit was used the conductor cannot be Reidentified as a hot. They are also too small to mark as hots.
All answers based on unamended National Electrical codes.
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04-06-2016, 06:30 PM #4
Re: Color coding fiasco
Wow, besides the obvious problems thats pretty nice compared to what I normally see. Panels around here typically have every color of the rainbow running all over.
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04-06-2016, 07:29 PM #5
Re: Color coding fiasco
Thanks for your replies, guys. I think this is a beautiful example of a fiasco.
1 - Well done with the bundling...until it gets into conduit
2 - Beautiful and neat organization of wiring colors...until you try to make sense of it
3 - and the colors are so transcendental, and healing... until somebody at the other ends gets a kick out of it
I say - it's far from fiasco, its dangerous...don't even know what's at the other ends.
I 'looked' at this for a friend who is taking over the project from the perpetrator. He's going to try to make some sense of it.
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04-07-2016, 04:32 AM #6
Re: Color coding fiasco
The metallic conduit is serving the purpose of the 4th conductor.
All answers based on unamended National Electrical codes.
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04-07-2016, 05:57 AM #7
Re: Color coding fiasco
He should pull all the pretty colors out, do some calculations, install as many mmore conduit runs as needed to address conductor size/rating/derating for ambient and number of conductors, then pull in the proper color conductors of the proper sizes, taking conduit fill into consideration too.
Is it an optical illusion or are some blue conductors being used for green grounding conductors?
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04-07-2016, 08:41 AM #8
Re: Color coding fiasco
Assuming that there is no problem with the conduit fill as Jerry pointed out (I can't tell the size of the emt or the conductors for sure) the easiest fix for the color fiasco would be a little black e-tape marker an inch or two from the breakers on the white wires. The lack of a locknut on the lower LB nipple is not such an easy fix however.
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04-07-2016, 09:40 AM #9
Re: Color coding fiasco
Yes Jim, but conduit fill is the concern
Jerry, yeah, I also think its a do-over. Add more conduit as needed to prevent the overfill, and put in the proper color coding. And, yes, there are a mixture of blue and green for the grounded conductors, and there is one blue wire that is an ungrounded conductor.
Mike, thanks for noting the other items. I'll be going over there to see if I can help point out all these items, because I'm pretty sure the local ahj isn't gonna be happy if it goes with just some colored tape.
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04-07-2016, 10:35 AM #10
Re: Color coding fiasco
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04-07-2016, 12:06 PM #11
Re: Color coding fiasco
Chris, my comment was directed at the post by Joe that has been deleted where he said the feed needed to be 4 wires. A 3 wire feed with a metallic conduit is allowed.
All answers based on unamended National Electrical codes.
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04-07-2016, 03:42 PM #12
Re: Color coding fiasco
This has been one of the most entertaining photographs I have seem in a long time.
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04-07-2016, 04:02 PM #13
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04-08-2016, 10:02 AM #14
Re: Color coding fiasco
1. This appears to be a sub-panel and should be 4 wire.
2. The equipment grounds should not be attached to the neutral busses. They should be attached to a separate ground buss.
3. Grounds and neutrals should be isolated from each other in a sub-panel.
4. I can't see the length of the raceway, so don't know if you need to de-rate the conductors. The 24" rule is correct.
5. A raceway can be used as an equipment ground, but not as a feeder ground.
6. You can use almost any color conductor as long it is identified at all terminations and at pull boxes etc.
7. The grounds and neutrals should only be bonded at the Main Bonding Jumper in the MDP. Not the meter base, wich is not a disconnect.
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04-08-2016, 10:46 AM #15
Re: Color coding fiasco
Seeing 6 double pole circuits and 6 grounding conductors per conduit the installation may be fine from a derating aspect. ten through 20 conductors gets a 50% of the original rating. Number 12 at 30 amps x .5 = 15 amp circuits. Can't read the breaker handles.
All answers based on unamended National Electrical codes.
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04-08-2016, 01:48 PM #16
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04-08-2016, 02:04 PM #17
Re: Color coding fiasco
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04-08-2016, 02:42 PM #18
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04-08-2016, 06:15 PM #19
Re: Color coding fiasco
While that may be remotely possible, it is highly unlikely according to 240.4 and its requirements and exceptions.
If they get temperatures which are 87-95 degrees F, the derating factor to apply to the ampacity in Table 310.15(B)(16), #12 AWG 90 degree C rated conductor insulation with a rating of 30 amps is derated in accordance with 310.15(B)(2) and Table 310.15(B)(2)(a) is 0.96.
30 x 0.96 = 28.8
12 current carrying conductors in each conduit requires a derating factor of .50 as Jim said
28.8 x .5 = 14.4 amps
The overcurrent protection needs to be installed in accordance with the conductors ratings or the name plate (with appropriate derating applied to the nameplate as the nameplate ratings do not include or account for any derating).
Added the bottom part with edit as I was fighting with 'database error' and 'time out error' messages.
Last edited by Jerry Peck; 04-08-2016 at 06:34 PM.
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04-08-2016, 07:49 PM #20
Re: Color coding fiasco
Discussion on ambient temperature.
Average Ambient Temp
All answers based on unamended National Electrical codes.
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04-08-2016, 11:06 PM #21
Re: Color coding fiasco
Mike, the NEC says he'd have to recolor every inch of those conductors, not just a bit near the ends.
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Mike, the NEC says he'd have to recolor every inch of those conductors, not just a bit near the ends.
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If our friend doesn't do it over, he's taking responsibility for every connector, every coupling, every end that should have bee reamed . . . unless, perhaps, the AHJ is willing to perform a transition inspection and sign off on part of the job. It had a permit open?
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04-09-2016, 06:19 AM #22
Re: Color coding fiasco
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04-09-2016, 06:30 AM #23
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04-09-2016, 10:57 AM #24
Re: Color coding fiasco
I read all 5 pages of that link and there is no consensus or method specified to determine the average ambient temperature. One person posted that San Diego average was 66 degrees, well under the adjustment temperature to apply adjustment. The OP was from Northern CA were it is even cooler.
All answers based on unamended National Electrical codes.
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04-09-2016, 12:39 PM #25
Re: Color coding fiasco
One person posted that when the temperature outside may be 90F, the temperature on the rooftop could be 130F.
Another person said "IMO it "should" be the max but then again should the duration of the Max also be a factor."
I agree with that person as, with heating due to bundling/lack of maintaining spacing, the effect is for a distance of "over 24 inches", thus it makes sense that the ambient temperature be based on highest temperatures for a specified number of hours.
Trying to apply cooler temperatures to a derating which is addressing heating just plain does not make any sense.
But, like I said, some electricians pooh-pah derating while the other electricians under the reason and need for it.
Think about more than 3 conductors going through a single hole in a wood top plate and the area around the conductors is sealed as required for fireblocking and that distance is not even the old 24" standard which applies to other aspects.
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04-09-2016, 06:13 PM #26
Re: Color coding fiasco
There is the exemption for less than 10% of the circuit length the adjustment does not apply for higher ambient temperatures.
All answers based on unamended National Electrical codes.
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04-09-2016, 06:40 PM #27
Re: Color coding fiasco
While I am missing seeing that 10% circuit length exemption, the typical ambient which creates the need for derating is high attic temperatures - and 50% or more of the conductor length will typically be in the attic for a single story house on a slab or crawlspace.
Do you have the section which gives that 10% circuit length exemption as I am not finding it (probably right in front of me and if 'it was a snake it would bite me' ... but I can't hear the rattle yet ... thanks). I've probably even read that 10% exemption before as it does sound familiar, just usually does not come into play may be the reason.
While the outside ambient may only be 85 degrees F, the attic during the summer can easily be well over 100 degrees F. And down here in Florida, and likely other states with a lot of sun, the attics can get to 140 degrees F. Those are the ambient temperatures which are the ones which typically need to be accounted for.
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04-09-2016, 07:07 PM #28
Re: Color coding fiasco
Robert Young's Montreal Home Inspection Services Inc.
Call (514) 489-1887 or (514) 441-3732
Our Motto; Putting information where you need it most, "In your hands.”
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04-09-2016, 09:20 PM #29
Re: Color coding fiasco
The neutral conductor of a branch circuit must be identified in accordance with 200.6 [210.5(A)]. Equipment grounding conductors can be bare, covered, or insulated.
Insulated equipment grounding conductors size 6 AWG and smaller must have a continuous outer finish either green or green with one or more yellow stripes, in conformance with 250.119 [210.5(B)]. On equipment grounding conductors 4 AWG and larger, insulation can be permanently reidentified with green marking at the time of installation at every point where the conductor is accessible [250.119(A)]. Ungrounded conductors must be identified as follows [210.5(C)]
The OP (All circuit breakers were for new HVAC units at the rooms.)
Does :230.71. apply?
Just asken, not wishen or hopen.
Also, from Mike Holt's EC&M, Identification can be by color coding, marking tape, tagging, or other means approved by the AHJ.
Robert Young's Montreal Home Inspection Services Inc.
Call (514) 489-1887 or (514) 441-3732
Our Motto; Putting information where you need it most, "In your hands.”
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04-10-2016, 08:31 AM #30
Re: Color coding fiasco
Adjustments and exemptions.
Conductor Size Matters, minimum size requirements
All answers based on unamended National Electrical codes.
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04-10-2016, 09:53 AM #31
Re: Color coding fiasco
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04-10-2016, 10:21 AM #32
Re: Color coding fiasco
To properly phrase the 10% exemption: (bold and underlining are mine)
Exception: Where two different ampacities apply to adjacent portions of a circuit, the higher ampacity shall be permitted to to be used beyond the point of transition, a distance equal to 3.0 m (10 feet) or 10 percent of the circuit length figured for the higher ampacity, whichever is less.
Thus, if there is a circuit which is 5 feet up, 50 across the attic, 6 feet down, and then 25 feet around a room, the maximum allowed length to be used at the higher ampacity rating would be 3 feet the entire circuit would need to be derated.
Let's change the numbers around: 5 feet up, 6 feet across the attic (over a bathroom, for example), 5 feet down, 20 feet around a room - still only allowed to have 3 feet at the higher ampacity, so the entire circuit would need to be derated.
Let's change the numbers around yet again: 5 feet, 3 feet across the attic (over a hallway, for example), 5 feet down, 20 feet around a room - still only allowed to have 3 feet at the higher ampacity ... which we have with 3 feet across the hall ... the circuit does not need derating.
Of course, though, with a hallway being 3 feet minimum between the walls, the conductor length in the attic would be 4 to 5 feet, but if the length around the room was 40 feet and the length up and down the wall was 5 feet each, the 10% length would be 5 feet, and would be okay.
But what electrical contractor in their right minds would want to go to all that trouble, only to find out that their calculations were wrong and they now had to replace that wiring?
There are applications for that 10% exemptions, but it would likely not be in a residential setting.
Let's say you ran four 33 foot circuits in conduit, the first 3 feet of circuit in a single, larger, conduit to a junction box which then went to four separate conduits ... you would be required to derate for that first 3 feet as it exceeds the 24 inches for conductors in the same conduit, but ... that exception says that you can extend the higher ampacity out from the transition point for 10 feet or 10%, whichever is less, and with 10% being 3 feet, you can apply that 3 feet to the first 3 feet in the single conduit and ... not have to apply derating to that circuit.
EDIT: Corrected the example immediately above with edit as I had a "30 foot circuit" and changed it to "33 foot circuit", otherwise, taking off the "first 3 feet" would only have left 27 feet, and 10% would only have been 2.7 feet ... corrected the example to make it work for the exception.
Last edited by Jerry Peck; 04-10-2016 at 10:45 AM. Reason: see EDIT
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