Sb2500 g59

[Gavin A]

Designed & Installed over 850kWp is that long enough?
Electrical engineer for last 25 years is that long enough?
Just got caught out with lack of equipment supply due to the friggin deadline, and had to modify system to suit availability (it is a single phase install so Tripowers wouldn't work) fitting a G59/2 control panel now,
just wanted to know if you could change all the settings using my grid guard code and save me the cost of a panel.

I think you probably can, but you'd have to do the additional testing needed for none type tested G59 kit. Personally I'd just get the guys at G59-test.co.uk to do that testing and sign it off, but if you're a time served electrical engineer you may be capable of doing the tests yourself - I just couldn't get my head around how to do the test, what test kit I'd need etc so went with the specialists.

 

[Gavin A]

If the inverters are the SB2500HF, then yes, as you can connect by bluetooth you can change the individual parameters to G59 settings, but I do not believe they have G59 certification so you would probably need a separate G59 relay to satisfy the DNO.

If they are the older design, SB2500, then you cannot connect by bluetooth 'out of the box' so cannot easily adjust the parameters. However, looking at the installation manual it does imply that you can change the country settings etc with appropriate software and hardware so might be possible. Again they have no G59 certification so I think you will be forced to get a G59 relay.

you can connect with a wire to the coms port - I've got one kicking around but haven't really needed to use it for ages as HF & TL took over.

the test cert is only a type test certificate, no reason why you can't produce your own test cert for each inverter if you're capable of doing the tests. It's no different to having to test the G59 relay (unless you're buying one with test certs already).

personally I don't understand the concept of the G59 relays anyway, as it entirely defeats the purpose of the different standards to have a G59 relay that will never ever do anything, while the inverters themselves still cut out at the tighter G83 standards... but I have fitted one once because the DNO wouldn't see sense.

 

[SolarCity]

personally I don't understand the concept of the G59 relays anyway, as it entirely defeats the purpose of the different standards to have a G59 relay that will never ever do anything, while the inverters themselves still cut out at the tighter G83 standards... but I have fitted one once because the DNO wouldn't see sense.

Agreed. But is it not the case that the inverters should have their settings relaxed so that the G59 relay operates correctly?

 

[BruceB]

personally I don't understand the concept of the G59 relays anyway, as it entirely defeats the purpose of the different standards to have a G59 relay that will never ever do anything, while the inverters themselves still cut out at the tighter G83 standards... but I have fitted one once because the DNO wouldn't see sense.

Then your DNO did not understand their own standards if they said put G59 protection in series with G83 protection. It will not behave properly. Although the G59 voltages are tighter than the G83 voltages, the G59 frequencies are looser, specifically because the do not want G59 generators cutting out too soon and causing instability. If you have a G59 relay, then the settings on the inverters should be left outside the G59 limits.

 

[powervan]

Bruce B (U R THE MAN) u sure ur not worcester come back in another life

 

[BruceB]

No, we were here at the same time. He iirc is a chartered civil or structural engineer and runs a big company. I am a chartered electrical engineer and run a small company.

 

[powervan]

Bruce BIG isnt always best !! tell the wife all the time !!

 

[Gavin A]

Then your DNO did not understand their own standards if they said put G59 protection in series with G83 protection. It will not behave properly. Although the G59 voltages are tighter than the G83 voltages, the G59 frequencies are looser, specifically because the do not want G59 generators cutting out too soon and causing instability. If you have a G59 relay, then the settings on the inverters should be left outside the G59 limits.

I tried to point this out to them, but tbh I got the impression they didn't care as long as they could tick the appropriate box and make us spend an extra grand on the G59 protection unit and testing.

 

[BruceB]

Of course I should have known you knew that anyway! It is irritating when they try to push you around because they can. I regret to say I do not fight every battle offered to me as life is too short to spend all of it getting wound up by others. But every now and then I do and it is satisfying to see them fold.

 

[pvman]

I was having a chat with a man from the dno (sse) today and he was sure that from next month there will be no g59/2 installs and we will all have to go back to the relay units and expensive tester hire. His reason was that they can't test the inverters themselves,

I was going to point out that they rely on the certificates for the test meters but I saved my breath.

Tom