Solar inverter clipping

Sterlingtimes

For the first time for many months, I am seeing power output clipping. My absolute clipping level results in 770 Wh being produced in 15 minutes or 3,080 Wh being produced in an hour. This falls a long way short of my DC panel specified output of 3,780 Wh. I rather presume that my solar installer, TP Solar (now defunct), installed M215 rather than M250 Enpahse micro-inverters (difficult to know), but even so I would expect a higher output.



Are others seeing clipping nearer to 90% of the DC output of their panels rather my 3,080/3,780 = 81%?

This rather adversely affects my "O" calculation.

Martyn1981

Hiya Sterling. Is there any chance this is deliberate, in the same way that some installers recommend an inverter that is 10% to 20% undersized to get the most out of UK generation?

I admit it looks odd, but April power can be some of the best due to great sun and cold. I noticed yesterday that my systems sustained 4.3kW for about 5 mins, when I was pretty sure that 4.2kW was the best I'd ever see, so probably down to cold wind.

Not saying they are the right micro's, I honestly don't know, but was wondering if 215 v's 250 (86%) was deliberate, if ...... and only if ...... the undersizing rule* applies to micros too?

*Losses to capping are more than made up by higher generation due to efficiency gains at lower generation times.

Mart.

Sterlingtimes

Martyn1981 wrote: »

Hiya Sterling. Is there any chance this is deliberate, in the same way that some installers recommend an inverter that is 10% to 20% undersized to get the most out of UK generation?

Mart.

Thank you, Mart, that is an interesting angle that you raise. Indeed it is only in the very best conditions that the clipping occurs. This means that the loss through clipping or maxing out is quite small. In effect, however, my system is delivering a maximum of 80% of 3,780 panel rating. It may partly explain whether my daily Os are a little below others.

michaels

I have the same set up (and the same installer, Paul Page is a crook, look at companies house TP kitchens, Trade Price Solar etc).

What should I look for on the Solar Edge output portal to see if I am suffering the same issue?

Sterlingtimes

michaels wrote: »

I have the same set up (and the same installer, Paul Page is a crook, look at companies house TP kitchens, Trade Price Solar etc).

What should I look for on the Solar Edge output portal to see if I am suffering the same issue?

If you look at my graph above, you will notice that the curve around about the middle of the day becomes flat.

Exiled_Tyke

michaels wrote: »

I have the same set up (and the same installer, Paul Page is a crook, look at companies house TP kitchens, Trade Price Solar etc).

What should I look for on the Solar Edge output portal to see if I am suffering the same issue?

If you've got a Solar Edge inverter then presumably you have optimisers installed rather than micro-inverters so it's not quite the same set up?

How does your peak output compared to both the panel and inverter ratings.

I have found that in optimum conditions my best performing panels peak at just over their rating (311W compare to 300W rating). My inverter has also peaked at about 3.5 Kw even though it's rated at 3Kw. Although this hasn't appeared on the dashboard but viewed on the inverter display panel.

Of course the simplest check is to check the inverter is the one you were quoted for: Mine is an SE3000. There should be a small sticker/panel on the right hand side of the inverter with these details on.

Even though I've had some great peaks in performance I never seem to get the same outputs as others on here and am consistently below the PVGIS estimates.