Phase rotation - CBA vs ABC

Question

Started a new job writing software for a company that does some power metering and I'm trying to wrap my head around this whole phase rotation thing.

So, I understand there are 3 phases and they can be in two different orders (ABC/CBA or ABC/ACB depending on the convention you prefer).

In my specific case, I have a power meter that might spit out the following:

Iaɵ - 341
Ibɵ - 223
Icɵ - 103
Vaɵ - 0
Vbɵ - 240.8
Vcɵ - 120.8
PFa - 0.95 capacitive
PFb - 0.94 capacitive
PFc - 0.95 capacitive

The goal is to draw a phasor diagram to properly represent this data. I wrote something quickly to generate this:

However, I am being told that the rotation on this is incorrect by one of the EEs on staff and that he can determine this simply by seeing that the power factors are listed by the meter as capacitive rather than inductive.

Anyone able to explain to me exactly how to plot these values correctly and how exactly ABC vs CBA rotation plays into plotting the phasor diagram in the correct manner?

Answer 1

There are two common conventions of phasor rotation, which is either ABC counterclockwise or ACB counterclockwise. Any AC system strictly adhere to one of this for all their protective/metering devices.

1. The phasor displayed by you above clearly show ACB counterclockwise AC input phasor, if the input is not counterclockwise then your programme is wrong.

2. The phasor is curiously showing leading current angle, unless you are sure the load input to the meter is capacitive if not the programme is not correct. Better said 99.9% of Electrical loads are inductive thus expected current angle should be lagging voltage, hence there is need to check your input parameters for the software you are using/developing.

Answer 2

ELI and ICE answer your question. Your current angle should be leading the voltage in a capacitive circuit. You've drawn a lagging current with a capacitive load. This is incorrect.

Answer 3

Based on what is shown it looks like your software is correct. If the power factor is, as your EE says, in fact inductive you may have the phasing for the inputs on the meter swapped (IA/VA as shown is actually IC/VC and IC/VC is actually IA/VA).