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Another noob looking for help

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Hello all,

This is my installation which has been running since just before lock down in Pretoria. My home is a small, two-bedroom unit.


·         18x 340W/375WP A++MULTIC PERc SCHR 50VP panels

·         2x HYBRD SMRT+SchAexKl 5KW 48V9KVAP 6KVAP MPT 1/3PHAPROG manufactured 12 2019 from the label

·         8x Schubart 6-GFM-240J 12V 240AH

·         1x Geyser collector panelRetr150/215LP BlackCobal2M EFFITEMP/HP

·         1x Circulation G-Pump 12VDC 10L/min2.5M head 100CelsiusBR

·         1x Solar panel 10 Watt SM ADVANCED A+GRAD 18 VOC

Previously installed GeyserWise


The driving force for going solar was to limit payments to ESKOM (zero if possible) and overcome the frustrating, random load shedding episodes we had earlier in the year (remember them?). Cost-benefit was not the main issue although the thought of excessive ESKOM price hikes and worse load shedding in years to come was a consideration.

During lock down I have tinkered with some settings and hooked up a laptop to get a log from WatchPower but don't really know what I am doing. As others have noted, the pdf output is not much use. I have recorded metered kWh daily and find a range of between 4 and 8. This is partly because of household routines that are not going to be easy to change, like doing the washing at 5:30 instead of midday.

Based on what I am trying to achieve, namely minimum grid use, please help with settings of the inverters. The installers told me that it was best to leave settings at factory defaults. When I asked them about firmware updates and they told me that the units would have to be taken back to the suppliers for updates, I knew I was on my own! (I don't want to update firmware).

I have noticed that there is often a 'spike' or 'dip' in the current in the early evening as if the switch from solar to battery or battery to grid is not as smooth as it should or could be. Rather than try to sort that out on its own I would rather ask for help. There are dependencies between the settings, as I have read here. Your help will be appreciated.

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  • 2 weeks later...

Hello all, maybe 'introduce yourself' was not the best place for this post but i won't cross post.

Possibly @plonkster , @Pietpower , @Coulomb or someone else would care to comment first on whether I can benefit from fine-tuning the inverter settings based on the installed capacities of batteries and panels and my stated aim?

Thanks a lot,



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Since you are running Watchpower, you presumably have an Axpert or clone. It sounds like you are using the SOL output source priority (setting 01). That's best for load shedding readiness, but not for minimising Eksom use. Try SBU if you have that option.

The other thing is to check that the battery is getting fully charged. Watch the battery voltage, and make sure it stays around 56 V or so for at least an hour on a good solar day, and doesn't head for around 54 V (float voltage, charge LED on solid) before that solid hour or more of 56+ V. Chronic undercharging of a lead acid battery will quickly ruin it, and of course you won't save much Eksom usage.

Edited by Coulomb
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Hello @Coulomb, Thanks for replying. It seems like a clone and I have set SBU.

On a good sunny day battery reached 53.9 - 54.1 on the display. I changed 27 Float to 56.0 (it was 54) and now the reading is 56). That was easy!

I know the settings are interrelated. Could you give better suggestions for 26, 29 and maybe others? They are still on factory settings. For example, would 16 OSO save Eskom use?


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11 hours ago, 8321 said:

I changed 27 Float to 56.0 (it was 54) and now the reading is 56). That was easy!

I guess that's one way of doing it. You have the chance of over-charging the battery, but since 56 V (14 V per 12 V module) is under the gassing voltage (14.4 V per 12 V module at 25°C), it should not be too damaging. Certainly better than chronically under-charging the battery.

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5 hours ago, Coulomb said:

56 V (14 V per 12 V module) is under the gassing voltage

14V is a gassing voltage, but certainly at much lower levels than absorption voltages (eg 14.5V). If I recall 13.2V is considered a non-gassing voltage, but that is only to be used with a battery that is in "storage", not one that is actively cycled.

I don't see a problem with a higher float voltage, especially if the batteries are cycled daily and absorption finishes late in the day.

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