Inverter stats slightly higher than generation meter

chamelion

Hi folks,

I've noticed that the readings / stats of my inverter's portal shows as higher than my meters - about 8% or so.

The manual of my inverter appears to have a way to 'tweak' / calibrate on pg 34/35 - at least I think that's what it means.

My theory is that I can set it as "over excited" and set the power factor value to 0.95 (as a start) and tweak as needed.

Does this make sense or does over excited do something completely different (and something I shouldn't touch?!).

Thanks!

Dave_Fowler

chamelion wrote: »

Hi folks,

I've noticed that the readings / stats of my inverter's portal shows as higher than my meters - about 8% or so.

The manual of my inverter appears to have a way to 'tweak' / calibrate on pg 34/35 - at least I think that's what it means.

My theory is that I can set it as "over excited" and set the power factor value to 0.95 (as a start) and tweak as needed.

Does this make sense or does over excited do something completely different (and something I shouldn't touch?!).

Thanks!

It's nothing unusual for there to be a discrepancy between the official generation meter (TGM) and the value shown on the inverter. The inverters are not calibrated accurately. My inverter reads about 2% high.

I would not recommend changing the pf setting on your inverter. The grid expects a pf of 1. I think changing the setting would actually make things worse because the TGM reads 'real' power and if you generate out of phase, the TGM would read even lower.

Dave F

legoman62

chamelion wrote: »

Hi folks,

I've noticed that the readings / stats of my inverter's portal shows as higher than my meters - about 8% or so.

The manual of my inverter appears to have a way to 'tweak' / calibrate on pg 34/35 - at least I think that's what it means.

My theory is that I can set it as "over excited" and set the power factor value to 0.95 (as a start) and tweak as needed.

Does this make sense or does over excited do something completely different (and something I shouldn't touch?!). T


Thanks!

My SMA inverter over reads by 1% compared to gen meter.
I have the option in settings to periodically reset it correctly:)

pinnks

My SMAs also read about 1% high. I have thought about resetting total generation at, say, year-ends but have decided not to bother...:beer:

EricMears

My TGM actually records more than my SMA inverter. Not a large discrepancy - I think it's about 30 kWh out of 22,600 kWh.

Every chance that both are slightly wrong - even the (allegedly) accurate TGM would have an allowable error of something in the order of 1 or 2% and it's just a fluke that the even less tightly specced inverter meter gets so close to it.

Martyn1981

My old SMA's both under-read by about 1% & 3%. Their Solaredge replacement, and the older Solaredge inverter I have, both over-read by about 2%.

8% is a bit high, but somewhere in the info it'll almost certainly state that the figures are only for guidance and not to be relied upon.

As Eric says the TGM's can be wrong too. They are import meters and I think the tolerance for import meters is +1% and -2%, so it protects you from too much over-reading on your leccy bill, but in the situation of us wanting as much PV gen as possible could lose us up to 2%. Oh well.

JKenH

My inverter readings taken from 2 different monitoring apps are between 5 and 10% lower than my generation meter. My old inverters were pretty much on par with the TGM.