Can we extract the Zero Sequence Unbalance Factor (ZSUF) from an ION8650 power meter (or any PQ meter for that matter)?

[sesa360183_brid]

ZSUF = zero sequence components of voltages / positive sequence components of voltages

Maybe via VIP, ION configuration, or some register I have to look for?

This is a customer requirement. The customer requires Negative Sequence Unbalance Factor (NSUF) and ZSUF. As I checked in SE references, the voltage unbalance measurement that is used and displayed by our PQ meters is the NSUF. Now, I just need the ZSUF to fully comply with the requirement.

Any assistance/insight will help. Thank you very much!

[sesa56307_bridg · Accepted solution]

If I understand correctly, ZSUF and NSUF are the same as the supply voltage unbalance parameters defined in the IEC 61000-4-30 power quality standard, which states:

"u0 = (U0 / U1) * 100% = (zero sequence / positive sequence) * 100%"

"u2 = (U2 / U1) * 100% = (negative sequence / positive sequence) * 100%"

The ION8650A does measure these values according to the requirements of IEC 61000-4-30.  I believe the meter provides these measurements as 3-second values, 10-minute values, and 2-hour values as per the aggregation requirements of IEC 61000-4-30.  The historical values should be logged in ION data recorders named "4-30 2hr Log" and "4-30 10m Log", as well as "4-30 3s Log" which is disabled by default.  If you are looking for the measurements themselves, they are calculated in the default ION framework on two ION Arithmetic modules named "Sequence Comp1" and "Sequence Comp2" as follows:

"Sequence Comp1" module has output registers for "NegSeqComp 3s", "ZeroSeqComp 3s", NegSeqComp 10m", "ZeroSeqComp 10m"

"Sequence Comp2" module has output registers for "NegSeqComp 2hr", "ZeroSeqComp 2hr"

I hope this helps.  It does seem to be aligned with your description of ZSUF and NSUF.  There may be other ways of getting at this data in your system (e.g. 4-30 report in PME), but the meter certainly does calculate the values you describe.

Best regards,

David Tuckey, Firmware Architect

[Yut]

Please open Designer then take a look at IEC 61000-4-30 Power Quality Framework see the two Arithmetic Modules, Sequence Comp1 and Sequence Comp2 you have two choices of calculation.

I recommend everyone who will work with the PQ study the framework thoroughly there are many thing more than the document.

[sesa360183_brid]

Thank you very much, David, for the detailed response!

Will try this solution when I go back to the site.

[sesa360183_brid]

Will definitely consider this, Yut. This is very much in line with David's answer above as well! Thank you very much!