Orange w/ Blue or Blue w/ Orange
- Thread starter crp123
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richwaskowitz
Senior Member
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- Shelby Twp. MI, near Detroit
Sounds Familiar
Sounds Familiar
We have had this discussion here (UL Panel Shop) before and have asked UL for their opinion. Since UL 508A does not address identification by color for DC control circuits which also remain energized when the main disconnect is in the off position, we have reverted to orange (or yellow). There opinion was that if it were required to use two colors, it would have been so stated in UL 508A 66.9.
Sounds Familiar
We have had this discussion here (UL Panel Shop) before and have asked UL for their opinion. Since UL 508A does not address identification by color for DC control circuits which also remain energized when the main disconnect is in the off position, we have reverted to orange (or yellow). There opinion was that if it were required to use two colors, it would have been so stated in UL 508A 66.9.
ORG/BLU or BLU/ORG
Either way you can't identify the grounded conductor.
It doesn't prohibit you from BLU/ORG WHT/ORG even though WHT/ORG is called out for AC grounded.
It does prohibit ORG/BLU ORG/WHT since a WHT stripe cannot be used on ORG. And this gets you in trouble with 13.2.3.2 (3) because the stripe must be BLU to match the ungrounded.
You can go BLU/ORG WHT/ORG; Isolate the DC from the AC physically which is good practice anyway; Tape mark the grounded DC WHT/ORG with BLU tape at the terminations and maybe BLU terminal blocks.
The alternative is to go ORG/BLU to emphasize the energized portion; then WHT tape the grounded conductor. You might also consider BLU and WHT terminal blocks.
A safety purist may demand ORG predominate to prevent a shock hazard. I favor the BLU leaving ORG for the real danger from the AC circuits. Since my DC is 24V the typical energized hazard is they pop the supply. I also can use the BLU terminal blocks and avoid tape marking on most ends.
Either way you can't identify the grounded conductor.
It doesn't prohibit you from BLU/ORG WHT/ORG even though WHT/ORG is called out for AC grounded.
It does prohibit ORG/BLU ORG/WHT since a WHT stripe cannot be used on ORG. And this gets you in trouble with 13.2.3.2 (3) because the stripe must be BLU to match the ungrounded.
You can go BLU/ORG WHT/ORG; Isolate the DC from the AC physically which is good practice anyway; Tape mark the grounded DC WHT/ORG with BLU tape at the terminations and maybe BLU terminal blocks.
The alternative is to go ORG/BLU to emphasize the energized portion; then WHT tape the grounded conductor. You might also consider BLU and WHT terminal blocks.
A safety purist may demand ORG predominate to prevent a shock hazard. I favor the BLU leaving ORG for the real danger from the AC circuits. Since my DC is 24V the typical energized hazard is they pop the supply. I also can use the BLU terminal blocks and avoid tape marking on most ends.
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