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Metering Readout Problem

Metering Readout Problem

Metering Readout Problem

(OP)
Hi to all,

I would just like to ask your inputs with regards to the metering readings in the attachtment.

What problem does this reading pose?
What are the possible causes?


Any input is well appreaciated.


Thanks!

RE: Metering Readout Problem

To save everyone the trouble, the contents of the file are below. There's no need to download the file or to run Excel.

Quote:


Metering From LCD

IA = 136.8A @ 150deg
IB = 136.4A @ -150deg
IC = 136.8A @ 90deg
IN = 0A @ 150deg
IG = 262.8A @ 149deg

VA = 7.77kV @ 0deg
VB = 8.02kV @ -121deg
VC = 7.94kV @ 121deg
VS = 0.226kV @ -166deg

I1 = 45.1A @ -30deg
3I2 = 271.6A @ 150deg
3I0 = 261.4A @ 149deg

V1 = 7.92kV @ 0deg
V2 = 0.013kV @ 161deg
3V0 = 0.422kV @ -154deg

Power Factor
A = -0.86 lag
B = 0.87 lag
C = 0.85 lag

RE: Metering Readout Problem

That you need to swap the polarity of IA?

RE: Metering Readout Problem

I'd be looking to reverse IA too.

It will be causing power to be recorded incorrectly.

RE: Metering Readout Problem

Another vote for turning IA around.

Good on ya,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies

RE: Metering Readout Problem

I agree with the Ia polarity issue. What is the expected direction? All currents are shifted 180 deg, which may be entirely accepted for the application, but worth pointing out.

RE: Metering Readout Problem

(OP)
LiteYear,

Thanks for the favor, well appreciated.



To all who replyed, thank you.


We'll be checking connections by the earliest possible time - plant in operation right now.




smallgreek,

Application is protection relaying w/ SEL 351 sir.

RE: Metering Readout Problem

If you are using any of the Directional (67) elements of the SEL-351, best to get your phasing sorted asap.

RE: Metering Readout Problem

If you are concerned about Watt/Var direction, this could also be a concern. Ie, generators consider +Watts to be one thing, feeders, another. Find out if you are concerned about consuming / producing watts/vars. It may be the case that all CT's are reverse polarity, in addition to the Ia polarity issue.

RE: Metering Readout Problem

(OP)
rterickson,

sir, as per setting, 67 elements are disabled. i will verify this setting with designer asap.

Thank you.


smallgreek,

thank you for pointing that out sir, i will also confer this to the designer.

Lots of thanks!

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