Suuny Boy inverter SB3000 HF-30

[SolarCity]

I think it takes underspeccing the inverter a bit far. I would have used a 3.6 inverter on this one

It's on the limit as far as I'm concerned. I generally go for 120% and no more. This is just personal choice though and until we get any solid empirical data from UK conditions then none of us are going to know for sure.

 

[dsa1000]

We recently installed 14x 245watt mono modules =3.4kw system using a SMA 3000HF, this was used by sma sunnyboy design am as best efficiancy and also for system, we installed it on one string with no shading and also a SSw roof at 39deg.

 

[dansk]

Im wondering if the OP is mixing up the "two rows" of panels as "two strings" because PV-SOL wont allow me to input two strings - also no over-voltage here even with VOC @-10 and 1000w/m² irradiance.

 

[MickF]

Ok. Here's Philip's photo. Any comments? Looks pretty neat except for a possibly peeling label?
Looks like a single string as well.

I thought that the DC and AC cables had to have physical seperation, looks like even if for a small distance they are in the same conduit.

Where's the emergency shutdown procedures?

Where's the Isolation stickers?

Where's the schematic?


Looks can be deceiving..

 

[moggy1968]

the emergency shutdown procedure has to be displayed at the point of interconnection, I.E the main fuse. I used to put it at the inverter as this seemed the obvious place, but got pinged for it on my previous inspection as the point of interconnection means between the suppliers side and the customers side, not the interconnection between AC and DC. HAving said that, could that flappy piece of paper be the shutdown procedure?

I think there are isolation stickers on there but it's hard to tell whats on them. The inverter should also have some stickers on it.

AC and DC should have physical seperation and I can't see how that would be achieved in this instance using the same piece of trunking, unless the cables go off in opposite (and rather unexpected!) directions.

It's not possible to tell if there are 2 strings from this, as there might be a connector bringing the 2 strings together further up the system. The best guide is probably the voltage readings because they will be about half what you would expect if it was one string.

 

[Gavin A]

tbf, I suspect the AC is going down, and the DC is going up in the conduit, so it's a relatively minor infraction of crossing the cables, and the inverter sticker looks like it's fallen off.

wiring diagram could be by the consumer unit, which'd be more sensible than the loft IMO.

Certainly far from the worst install I've seen pictures of

 

[moggy1968]

not sure if no seperation like that that would count as an observation or nonconformity, observation I suspect as you say it is probably just a cross over. Missing labels is an observation, as I know from my inspection today when stupidly I had missed one off!
The diagram has to be at the point of interconnection, which is the main fuse/meter position, which is often not where the DB is. I think thats because the diagram is regarded as for the use of the DNO.

But yes, none of these are major and overall it's a fairly tidy looking job, it's easy to nitpick!

 

[JulianC]

Re: AC & DC separation. Double insulated DC cable and insulated and sheathed flex or T/E is acceptable in the same bit of trunking is it not?

 

[moggy1968]

I actually can't see any refernce to physical seperation in 7671 or DTi Guide. It's one of those things we've always done, but now I'm thinking, do we have to worry about it!!

 

[SolarCity]

I actually can't see any refernce to physical seperation in 7671 or DTi Guide. It's one of those things we've always done, but now I'm thinking, do we have to worry about it!!

Likewise. I worried about induction from the AC cable but perhaps I'm worrying too much.

 

[Worcester]

Physical separation is a tick box on the commissioning report from the 2nd Edition guide, though which clause that comes directly from I have always been unable to trace! - As far as I am aware the only specific mention in the guide is the double ticked item 2.1.2 :

Double insulation (insulation comprising both basic & supplementary insulation, International Electrotechnical Vocabulary IEV 195-06-08), appropriate barriers and separation of parts must be applied to all systems with an open-circuit voltage of >120 Vd.c..

You might even be able to interpret that double insulated DC cables inherently achieve that requirement ....

Though it would be good practice anyway to keep them physically seperate, although the word and is important.