Phase Rotation Colors ?

[TwoBlocked]

Hi folks, first post. I like things "right" but never really expect them to be. I just try to leave things as "right" as practical. Sooooo, when hooking up a big ole SO cord with Black, Red, White (and green) for three phase power, is there a consensus on the phase colors left to right? Been doing some online searching and not finding much.

 

[Dennis Alwon]

There is no code on which colors to use however the standard for 3 phase 120/208 is black, red, blue. In your case you would have to mark the white conductor with any color other than white or green.

Whatever the color scheme in the building is then you should follow it when there are other voltages like 277/480

 

[kwired]

Your phase rotation meter probably has red, white, blue leads.

Have had POCO's mark service conductors red, white, blue for potential future reference if needed because that is what is on the rotation meter. Then EI questions why the white mark on an ungrounded conductor.

 

[Besoeker3]

For many years UK 3-phase colours were red, yellow, and blue. Primary colours. Now we have this nonsense:

For three-phase cables the phase colours are brown, black and grey, instead of red, yellow and blue, respectively, and the neutral colour is now blue instead of black. Again the protective conductor is identified by the colour combination green-and-yellow.

 

[texie]

Your phase rotation meter probably has red, white, blue leads.

Have had POCO's mark service conductors red, white, blue for potential future reference if needed because that is what is on the rotation meter. Then EI questions why the white mark on an ungrounded conductor.

I've always wondered why most phase rotation meters leads use white.

 

[Hv&Lv]

. I like things "right" but never really expect them to be.

And that’s the reason you never look at the colors and assume voltage or rotation.
Use a voltmeter and phase rotation tester always.

I have about 10 different colors tape. All it means to me is a way to identify the wire when installed.

 

[TwoBlocked]

Wow! Thanks for all the quick responses to a first-poster. I work in "gritty" industries, Gas Field and Old Manufacturing Plants. Likely to see nearly anything. Vrinstance, came across a system where the utility was 208 and they decided to run some exhaust fans 480 with a step up transformer. They installed a typical 480 Delta / 208 Wye transformer, but since they fed the 208 side, there was no place for a ground and so there is none... Yeah, I told them they need to put in a phase ground alarm.

Anyhoo, What I am asking about is not a code thing. It is a convention thing. I often see a Bk. Wt, Rd, Gn SO cord feeding a 480 3-phase panel or disconnect or starter. Yeah, the rotation might be anything and even if I phase taped, others could change a genny or whatever and so the rotation. So was wondering if you fine folks have seen or heard of a consensus in these installations for left to right or even rotation order. I am tempted to just strive for Bk, Rd, Wt rather than Bk, Wt, Rd to make it obvious that these are not 240/120 split phase installations.

 

[ActionDave]

I've never been a fan of color coding. I don't even like using black red blue or brown orange yellow for phasing. For a service or sub panel it is fine, but for things like line and load or a case where I'm feeding more than one piece of equipment out of the same conduit I'd rather use brown for load A, orange for load B, yellow for load C.

 

[LarryFine]

Welcome to the forum.

I would suggest first using a large blue permanent marker to re-identify the white conductor wherever exposed to make it obvious it's not being used as a grounded conductor. Then I would use it in the traditional black-red-blue color direction.

 

[TwoBlocked]

Sure, use blue tape or marker on the white when it is 208, but I am talking about 480. Probably cannot find a consensus because there is none.

Got embarrassed a while back changing out a 480 3-phase well pump with Bk, Wt, Rd SO cord installed from the manufacturer/rebuilder. Used the same colors from the old one for connecting the new one in the local disconnect. Didn't have much output, but the operator was sure that the screen in the creek was clogged so didn't try reversing it. Was called back later to do so. (Centrifugal pumps and fans will still work when running in reverse, but at a lower output)

 

[LarryFine]

Sure, use blue tape or marker on the white when it is 208, but I am talking about 480. Probably cannot find a consensus because there is none.

Unless you are wiling to re-color all three ungrounded conductors to traditional brown/orange/yellow.

 

[jim dungar]

I've always wondered why most phase rotation meters leads use white.

Many utilities use blue/red/white and at one time they may have been the primary market for phase meters.

 

[kwired]

Wow! Thanks for all the quick responses to a first-poster. I work in "gritty" industries, Gas Field and Old Manufacturing Plants. Likely to see nearly anything. Vrinstance, came across a system where the utility was 208 and they decided to run some exhaust fans 480 with a step up transformer. They installed a typical 480 Delta / 208 Wye transformer, but since they fed the 208 side, there was no place for a ground and so there is none... Yeah, I told them they need to put in a phase ground alarm.

Anyhoo, What I am asking about is not a code thing. It is a convention thing. I often see a Bk. Wt, Rd, Gn SO cord feeding a 480 3-phase panel or disconnect or starter. Yeah, the rotation might be anything and even if I phase taped, others could change a genny or whatever and so the rotation. So was wondering if you fine folks have seen or heard of a consensus in these installations for left to right or even rotation order. I am tempted to just strive for Bk, Rd, Wt rather than Bk, Wt, Rd to make it obvious that these are not 240/120 split phase installations.

Well since you are talking about flexible cord, you can use a cord with white conductor for something that doesn't require a grounded conductor yet are supposed to field identify that as an ungrounded conductor. Can also field identify all the conductors if you say have a BOY color scheme for 480 volts.

I will say I have seen flexible cord with no white conductor, Black, Red, Blue and Green. I imagine it can be purchased that way if you place a large enough order. Supply houses could purchase this way but I suppose don't get enough demand to do so is main reason why they don't.

 

[ggunn]

And that’s the reason you never look at the colors and assume voltage or rotation.

Always check.

A couple of years ago I had a PV system to design for a building where the service conductors were taped red, black and blue but the panel was loaded with two pole breakers that always left the same phase open. I asked the site assessor if he had checked the voltage but he hadn't. I did some research with the utility and found out that the building had originally been supplied with a 208/120V service but later the pole mounted transformer had been changed to 240/120V high leg. The customer's end of the service conductors never got retaped.

It's not just color coding that can mislead you; another time I had several systems to design for some schools. I designed them all for 480/277V services which was correct except for one school where they used 600V equipment like all the rest of them but it was serviced by a 208/120V transformer. Once again, our site assessor (different guy, different company) had not verified the service voltage.

 

[Hv&Lv]

Always check.

A couple of years ago I had a PV system to design for a building where the service conductors were taped red, black and blue but the panel was loaded with two pole breakers that always left the same phase open. I asked the site assessor if he had checked the voltage but he hadn't. I did some research with the utility and found out that the building had originally been supplied with a 208/120V service but later the pole mounted transformer had been changed to 240/120V high leg. The customer's end of the service conductors never got retaped.

It's not just color coding that can mislead you; another time I had several systems to design for some schools. I designed them all for 480/277V services which was correct except for one school where they used 600V equipment like all the rest of them but it was serviced by a 208/120V transformer. Once again, our site assessor (different guy, different company) had not verified the service voltage.

One of our site assessors did about the same thing.. didnt verify with the contractor and assumed 277/480.
the transformer was set and ready to be energized. I went out to look at the metering and noticed a label on the panel 208Y/120.
called quite a few people right quick to get this corrected.
The electrician knew his stuff and was good at his trade.
If we had energized this transformer he would have caught it before any breakers were flipped..
I was worried about the breaker ratings.

 

[Dzboyce]

Here's what my local inspector told me on a project. Since there are no NEC requirement for voltage color coding, I could use any color code I wanted. However if I had more than one voltage, in the system, then he wanted me to post a voltage color code on the panels. Like if I had a step-down transformer for 120 volt loads on a 460V 3 phase system.

 

[GoldDigger]

Here's what my local inspector told me on a project. Since there are no NEC requirement for voltage color coding, I could use any color code I wanted. However if I had more than one voltage, in the system, then he wanted me to post a voltage color code on the panels. Like if I had a step-down transformer for 120 volt loads on a 460V 3 phase system.

Whenever there is more than one voltage/phase system on site, the NEC requires the voltage and phase of wires by consistently identified and the coding used be clearly posted. But the NEC does not require that color be the basis for identification. Any other labelling method may be used.

 

[AdrianWint]

There is no way of knowing which is the 'first' phase.

While its true that your phase rotation meter will tell you that they peak in the correct sequence, it can't distinguish between black, red, blue or red blue, black or blue, black, red.

Incidentally, the first UK phase colours where RED, WHITE, BLUE (for no other reason than the colours of the UK flag). The WHITE was subsequently changed to yellow since white cores of that vintage turned to yellow with age.

 

[tom baker]

There is a simple solution to your color coding. You mentioned connecting motors, well pumps and panels, but portable cord is not allowed to be used as a substitute for fixed wiring, section 400.12
Run LTMF and with THHN/W in the appropriate colors.

 

[ggunn]

There is no way of knowing which is the 'first' phase.

What difference would it make? Only the rotation is important.