new service phase rotation

[malachi constant]

Project in the midwest, new construction of a municipal building. Reports from the site are that the electrical contractor wired the building counterclockwise and folks are expressing concern. The building system includes paralleled generators and a docking station for portable genset / load bank testing.

I am the engineer on the project, and know that the physics works just fine so long as everything up and down the line is wired the same way. What I don't know is how common or uncommon CW vs CCW is, and what concerns if any I should have. I've been around 25 years and have never even heard this question asked, so just am not sure what is typical or how big of a deal it is. Anything you all can teach me here is appreciated.

 

[infinity]

What do you mean by the contractor wired everything CCW? Did they swap two of the phases from the POCO?

 

[malachi constant]

What do you mean by the contractor wired everything CCW? Did they swap two of the phases from the POCO?

The email to me reads: "it was brought up this morning about the building being wired counterclockwise, which is apparently not the industry standard". That's all I know. I imagine the utility is wired standard. I have a meeting with them in a bit and will try to understand the situation.

 

[jim dungar]

The email to me reads: "it was brought up this morning about the building being wired counterclockwise, which is apparently not the industry standard". That's all I know. I imagine the utility is wired standard. I have a meeting with them in a bit and will try to understand the situation.

In my 50 years, I have never considered there being an industry standard rotation.

I have been in facilities where there has not been a consistent rotation standard from one room to the next.

 

[roger]

After the new service was energized whatever it was we kept the rest. We didn't care if it was CW or CCW.

 

[hillbilly1]

The email to me reads: "it was brought up this morning about the building being wired counterclockwise, which is apparently not the industry standard". That's all I know. I imagine the utility is wired standard. I have a meeting with them in a bit and will try to understand the situation.

Utility can be either way, most I have found have been CCW. It can be up to the electrical contractor to do a power down, and swap it to a desired rotation, but is extremely rare to change what the poco has delivered.

 

[infinity]

IMO there is no standard. As long as the EC kept the phasing the same as the incoming service there is no issue. I doubt that the POCO would even entertain changing anything on their end.

 

[hillbilly1]

IMO there is no standard. As long as the EC kept the phasing the same as the incoming service there is no issue. I doubt that the POCO would even entertain changing anything on their end.

Yeah, they most likely tell you to pound sand! LOL!

 

[zbang]

Same here, never checked or cared about the utility rotation, only that the motors spin the right way and however you guess, you'll be wrong 70% of the time . (It does become fun when 3-phase power tools are shuffled around to different shop locations and not all of the receptacles are wired the same direction.)

 

[LarryFine]

I see 3ph as delivered by the utility as arbitrary. You have to wire each and every piece to rotate correctly.

I never assume that all of the equipment will rotate the same direction just because I wire them the same.

 

[ptonsparky]

We checked rotation when/if Poco changed things on their end. They would make it match.
NWIH was I changing rotation on xxx number of motors.

New installations, I didn't care.

 

[Hv&Lv]

As long as the system rotation is turning the motor the correct way I wouldn't worry about it. Make the generator turn the motor the correct way also.
It's not like you are soft transitioning.

 

[malachi constant]

Thanks all. Sounds like the utility provided it as CCW, and the electrician only brought it up to the Owner because a UPS panel had to have phase wires moved to meet UPS requirements. Based on comments here I have no concerns.