advice for 3 phase connection

[xanderfh]

Fantastic job, I am tendering for a similar job at the moment - where did you put the string fuses and did the DNO require you to install a relay as you used TL inverters?

 

[calhalla]

Very good looking install and great attention to detail Worcester.
I would like to second russgibb and ask if a completed (sanitised) DNO G59 form could be posted to help us all out. We are dealing with WPD as well.
Regards,
Cal

 

[xanderfh]

Penny's just dropped, you are only running 2 strings per "array" hence no string fuses!!!

 

[Worcester]

Nope, there are 5 strings per inverter, each inverter has 4 identical strings to the 'A' mpp tracker and 1 slightly different string to the 'B' mpp tracker.

String fuses are needed and are built in to the inverter (optional ££ extra on most of the SMA TP range) makes install simpler and neater.

No relay needed as the inverters are all configured to G59/2 and DNO was happy (they've witnessed some of our other work before) they've now told us that they don't want to witness test any of our <50kWp installs if we use basically the same configuration.

 

[SolarCity]

String fuses are needed and are built in to the inverter (optional ££ extra on most of the SMA TP range) makes install simpler and neater.

What a great feature. I'll have to keep that in mind.

 

[Toonlad]

Steve,

Same as any other, unless you're using a dedicated G59 relay, then it's a simple case to test all the parameters that the relay should trip on (and not) at the same time as having it witnessed (over / under volatge, over under frequency, time to trip etc all as per the G59 spec). - Best to get a specialist firm in to do the testing unless you've giot a spare £11k to buy the testing kit. Usual charge about £500 / day plus another £500 or so for the DNO to witness the tests.

Thanks for the heads up Worcester,
I have since done a bit further digging, and advised my company directors accordingly,and added your comments. The way forward is getting the said advice ,me doing the course. Then get a specialist company to commissioning the first few,and me being shown/taught hands on every step of the way.Then we will probably invest in the test equipment, on further projects, and do it ourselves then.

ATB
Steve

 

[Worcester]

Then we will probably invest in the test equipment, on further projects, and do it ourselves then.

Thats if there are any G59/2 installs to be done after March next year

 

[xanderfh]

Many thanks for the reply, Ive just come from a Segan talk and have been enlightend to the fact that SMA inverters do have string fuses - I do agree it does look alot tidyer and im sure the additonal cost is worth it.

Lucky u, not having DNO witness another few hundred quid in the coffers!!!!

 

[Echo]

Great thread and a great example installation. How did you go about getting the cables into the property?

 

[jupestar]

That is a very neat installation, I can see the pre-planning that went into it.

I've seen some shocking installations - including unfortunately my Father's place. I've come to the conclusion eventually I'm going to have to re-scaffold and take the whole thing down.