Grid Voltage Too High - What can I do?

[SnaxMuppet]

Had the recorder installed today... removal next Wednesday or Thursday.

They definitely seem to be taking this seriously. While he was here this morning voltage was 248V. He said it was high but didn't think that they would change anything if it stayed below 254V. We will see...

[aloha]

263 volts is the tripping voltage of SMA SunnyBoys.

And the ESQCR's say that the maximum 230V voltage should be 253V.  If you run your voltage (or anyone elses) at >253 volts for any length of time (so thats short term transients excepted), then the ESQCR's are not being complied with.  This needs to be borne in mind when you set up your inverter parameters.

[Other-Power]

263 volts is the tripping voltage of SMA SunnyBoys.

And the ESQCR's say that the maximum 230V voltage should be 253V.  If you run your voltage (or anyone elses) at >253 volts for any length of time (so thats short term transients excepted), then the ESQCR's are not being complied with.  This needs to be borne in mind when you set up your inverter parameters.

Agreed, the 263 volts limit applies to transients.

[aloha]

And therefore the 10 minute average limit of 253V needs to be applied.  For systems with too high a grid voltage, or too high an impedance, the 264V trip setting will not resolve the issue, as when you get a sunny period, the production will up steadily, and so will the grid voltage if the impedance is too high.  Running continuosly at 263.5 volts all day is not a suitable way around dealing with a supply voltage or impedance that is too high!

[Other-Power]

Voltage flicker is directly proportional to source impedance.

High source impedance being due to long high voltage and or low voltage runs as well as high loading of a transformer, typical of Cornwalls distributed network.

So yes the 253 volts should be applied for durations and the 263 volts for transients (SunnyBoy should kick out a 261 volts)

Jonathan

[SnaxMuppet]

Update:

The result of the logger installed by the DNO is that they agree that the voltage is too high and they are adjusting it at the substation tomorrow! They will then install a logger again to confirm that it is then at an acceptable level.

RESULT!