Altering existing Installation

[jason121]

I think this has been talked about before, but will ask anyway.

I have be asked to remove the panels on a 4kw installation inverter SB4000TL -20
Ready for a new extension. The panels will have to repositioned east-west.
I believe the old SMA 4000TL-20 will be unsuitable and will need a 3000TL -21
Will the customer be still eligible for the existing old tariff or will I need to reissue a new MCS certificate. Thanks.

 

[whinmoor]

Seems ok to keep old tariff as long as it's the same panels and generation meter. The system size is unchanged so total capacity will be identical although output probably reduced.

 

[Worcester]

Try the Sun lounge for more extensive answers

 

[jason121]

Don't have a key

 

[Worcester]

The challenge is you need to ensure that you are not decommissioning it ....
Changing the inverter should need a G83 notification to the DNO.

 

[Gavin A]

The challenge is you need to ensure that you are not decommissioning it ....
Changing the inverter should need a G83 notification to the DNO.

does it? I thought that was only if it increased the capacity... least I'm fairly sure that's what our DNO said when asked.

I'm a bit confused why the inverter would need swapping mind, although it will be a bit oversized, surely that's not worth the cost of swapping it out... or are they funny voltage panels or something?

 

[Worcester]

You're attaching a different G83 type approved generator, nothing to do with capacity, and they want to know what equipment is connected where, it's just a formality, EXCEPT, that you need to 'decommission' in DNO's terms the old / replaced inverter.... can of worms..

 

[SolarCity]

As Worcester said, when we contacted DNO to ask about a similar situation we were told: replacing like-for-like inverter = no need for new G83. Replacing for different inverter = issue new G83.

 

[jason121]

does it? I thought that was only if it increased the capacity... least I'm fairly sure that's what our DNO said when asked.

I'm a bit confused why the inverter would need swapping mind, although it will be a bit oversized, surely that's not worth the cost of swapping it out... or are they funny voltage panels or something?

I am swapping the inverter because the 4000TL-20 is not a dual tracker inverter

 

[Gavin A]

I am swapping the inverter because the 4000TL-20 is not a dual tracker inverter

every 4000TL 20 I've ever installed has been a dual tracker, we must have installed well over 50 of them, and I've never heard of a single tracker version being made.

The only significant difference between the 4000TL-20 and the 4000TL-21 is the voltage range.

Turns out we've still got a 4000TL-20 datasheet on our website that confirms this. Now if it were the 3000TL-20, that'd be a different matter, as that was single tracker only, which is probably what you're thinking about.

 

[Gavin A]

You're attaching a different G83 type approved generator, nothing to do with capacity, and they want to know what equipment is connected where, it's just a formality, EXCEPT, that you need to 'decommission' in DNO's terms the old / replaced inverter.... can of worms..

actually, I may have just been thinking of times when we've had to swap out a faulty inverter with a replacement of the same make and model, which I suppose is a bit different.

 

[jason121]

in that case will leave in place, a little oversized for the job.

 

[Worcester]

in that case will leave in place, a little oversized for the job.

As the Aussies would say "Good Call"

 

[MATsolar]

Better oversized than undersized. Anyway, most of the inverters have better efficiency in part load conditions (and so does the SMA SB4000TL). You just have to assure to keep both arrays within the voltage range of the trackers...

 

[SolarCity]

Better oversized than undersized......

I disagree. Undersizing is often the most efficient way of matching an inverter.