VT wiring connections for ION 9000.

[Miyai]

Hello, 

Please advise on VT wiring connections for ION 9000.

Customer wants to record V0 waveforms.

Are the following wiring connections correct?

Also, should VN and VE be connected?

I have already explained to the customer that the V0 accuracy range is 57-400V.

Best regards,

Miyai

[DanL · Accepted solution]

That wiring and the term "V0" appear to correspond to the zero-sequence voltage.

With the usual definition of zero-sequence voltage, the 2nd set of PTs would require a ratio (either real or programmed in the meter) of 1/3 of the primary set.

Assuming the 6 PT's are all the same, it's trivial to simply configure the V4 PT ratio to be 1/3rd of the other ratio.

For wiring, I recommend ensuring the meter's VN connection be wired to the ground point shared for both sets of PT secondary's, everything else looks fine.

For configurations with PTs, the VE terminal will be unused, but we recommend you connect to ground anyway (usually the same place as the PT secondary grounding)

The voltage accuracy for the ION9000 under very low signal levels (voltage dips) is governed by the IEC61000-4-30 Class A specification:

+/-0.2% of Udin (aka. 0.2% of nominal secondary voltage)

[Miyai]

Hi @DanL 

Thank you for advice.

We asked the customer to consider the ground.

Regards,

Miyai