About three-phase unbalance standard designed by electricity company

[YKC]

Hello everyone,

From last question, I asked about the standard of unbalance of both voltage and current, since my manager asked me to collect them, please check the thread "About three-phase unbalance standard".

https://www.eng-tips.com/viewthread.cfm?qid=516148

Well, I got a new situation, collecting the standards from IEEE/IEC/ANSI was not enough, while my dear manager would like to take a look for the standards designed by electricity companies. For example, "Which electricity company" followed the formula of "Which Standard" to calculate the voltage unbalance and set the limited as "Which Value"%. However, due to the access limitation, I could not visit the website of electricity companies. I'm not sure whether those kinds of standards are confidential information or not. If not, could anyone please help me or inform me how to download those standards.

Thank you, and please have a nice day.
YKC
email: ken890309@gmail.com

 

[bacon4life]

Although the utility standards are unlikely to be classified as confidential, I doubt many utilities will publish what you are looking for in an easy to find location.

 

[Palletjack]

3% is the norm

 

[wcaseyharman]

A lot of utility companies in the US are highly regulated. The regulations you are looking for, as least in my state, are in the state administrative code and the state approved utility tariffs. That being said, I don’t recall that there is a specific requirement for my utility for customer imbalance, but I’ll have to check.

 

[YKC]

bacon4life, that's what I thought, I however still look for them.

 

[YKC]

Palletjack, could you please tell which company followed which standard to design this value (3%)? 3% as I know, some standard design this value in the area where has rich single-phase machine, so their tolerances must be high.

 

[YKC]

wcaseyharman, thank you in advance, please let me know if you got more information!!

 

[JJ_Roy]

One of the local utilities here has a 2% requirement. National Grid - Electric System Bulletin 750 (Section 3.9 Load Balance) "Voltage unbalance resulting from unbalanced currents shall not exceed 2% or shall not cause objectionable effects upon or interference with the operation of the Company’s facilities and service to others."

I believe ANSI C84.1 is 3% at the customer meter under no load conditions.