What is the proper way to flag the white conductor as a hot phase both at the panel and in the disconnect for 240v?

Is it the same as a 120v being a simple black flag on the white wire or should this be a red flag?

Further Detail if Needed:

I have a yet to be purchased A/C Condenser that will be a max of 5 ton.

During rough-in I ran 8/2 wire with ground (less than 20') to a 60amp disconnect. While I understand the breaker that will be installed at the source panel will be determined by the condenser unit I get, likely a 30 but no more than a 40amp breaker, I wanted to properly mark both hot conductors.

The 8/2 wire has a black and a white conductor. Being that there is no neutral for an A/C Condenser, I decided not to run 8/3 wire (which was not available).

  • 1
    Black or red should be okay. It is more to mark the white as hot and not neutral. Think it depends on what is handy, than a specific colour.
    – crip659
    Jan 28, 2022 at 20:58
  • 1
    Any hot color, red or black being most common, but "not gray, white or green" covers the actual colors to avoid. I prefer red as it's more clear that it's not just stray tape. And put your answer down below, @crip659
    – Ecnerwal
    Jan 28, 2022 at 21:05

1 Answer 1


assuming you are in the US.

simply wrap the white conductor with Any color Tape that is NOT White, Yellow/Green, Green, yellow, Gray.

Article 200 of the NEC covers identification of the neutral.

there aren't any codes for the hots just colors generally used by electricians for certain Phases in different types of Electrical power. I.E. 3 phase versus single phase.

Anyways. if you're in your home and have single phase then RED is the Standard color. both being black is fine. or blue. or orange. whatever color electrical tape you have that is not White or green.

some folks use a marker. they say it's more permanent.

  • Green striped with yellow is a ground color. Yellow is a hot color.
    – Ecnerwal
    Jan 28, 2022 at 21:06
  • Great info - I try to keep to best practices (and code for the most part) when dealing with electrical.
    – Richard
    Jan 28, 2022 at 21:11
  • @Ecnerwal, yes yellow is a hot color but can sometimes be found as the neutral for certain phase type applications. Triplex wire is commonly sold with a yellow striped or solid yellow conductor. its commercial electrician stuff. im a resi.
    – RadioSpace
    Jan 28, 2022 at 21:11
  • @Richard, Thank you. I've done too many panel changes where the Second Hot conductor wasn't phased. it makes it clear and reduces mistakes down the road. you are a gentleman and a scholar
    – RadioSpace
    Jan 28, 2022 at 21:16
  • @RadioSpace I identify phases not poles. 120/240V are poles and don't need distinguishing. I have an installation of two 1" conduits. The last guy put four 20A circuits in 1 pipe, four 28A/240V circuits in the other. Each is red/black. One guess what I found shriveled up in the dust at the bottom of the boxes LOL so the circuits cannot be distinguished. The new plan is to preserve colorspace. Each pipe gets black-black for circuit 1, red-red circuit 2, and two 120V circuits. The 120V colors differ, so you'll know which pipe. Jan 28, 2022 at 22:09

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