G59 connection

[yellowvanman]

SSE are saying:
'For installations between 16A (3.7kW) per phase and 10kW per phase SSE are happy for you to use equipment certified for use under G83 provided you apply G59 settings.'

What does this involve?

 

[BruceB]

You would have to compare the 2 documents. But one specific I do know because WPD have been specifying it for a while is that the upper freq for G59 is 51.5Hz whereas for G83 it is 50.5 Hz. Some inverters in that power range already have G59 certification so you can set them up easily, eg SMA. Others are probably rushing to follow suit. I know the Power One PVI-10.0-OUTD is being done imminently. If you have to set it up manually (rather than simply select G59) then you will need the right software to interface with the inverter and adjust each setting manually.
Regards
Bruce

 

[Worcester]

The whole problem is that G59 is a 'slacker' specification than G83, deliberately.

You want larger systems to be more tolerant of wider changes so that they don't suddenly switch in and out, cousing big grid variations, a few (at the moment) small G83 systems popping in and out doesn't matter - Hence the requirment for G83 Stage2 with installs at multiple (adjacent) locations.

However what they are asking you to do is to adopt G59/2, and tighten it slightly, makes sense, and we have accomodated that request.

Though I'm not sure that it wouldn't stand up if a big enough organisation decided to challenge it, i.e. they may say G83 or G59, and I reckon they'd probably win - with enough £ and b*lls to do it. Otherwise what's the purpose of the standard?

As an aside, has anyone put a design forward to a DNO using say 6 G83 inverters and a G59 Relay?
(like the one from Control and Power Systems Ltd : NEW G59/2 PANEL )

I don't see how that could be compliant as the G83 with its tighter spec would effectively overide the G59.

 

[JD6400]

Hi Wocester

We have a site awaiting commissioning with 6 , Fronious ig 120 plus on 60 kw of schott and a separate 3 , Fronious ig 120 plus on 30 kw of sharp all on one site but with 2 separate heads .
Each one has to have a G-59 relay , there has been no issues raised yet , i say yet nervously !

 

[Worcester]

@dpelectricalltd,

Thanks for that, lets hope it works out for you.

Becasue if you think about it the G59 spec (and G83) covers all types of generators, not just inverter type installations. We are just all deep into solar PV on this forum, so It's going to be interesting to see how they (the DNO) interpret it.

 

[JD6400]

Thanks Worcester
Interestingly the company we use for the G59 relays always make a point of asking if it is for solar , will ask why next time i speak to them ?