Alpha Ess M48112-S 5.7kWh - 'Commercial/Industrial' designed for series.

WIAWSNB

But any reason they won't also work in a domestic situation in parallel?

I think the essential Q is, will the COM port communication be compatible with a domestic AC-Coupled inverter/charger such as the Sofar ME3000?

https://www.alpha-ess.co.uk/images/datasheet/M48112-S.pdf

QrizB

But any reason they won't also work in a domestic situation in parallel?

Nothing immediately springs to mind, and the info in that datasheet doesn't raise any immediate red flags.

Fundamentally, though, it'll be a case of caveat emptor. You'll be buying used batteries without specific instructions/guidance for your intended purpose, at your own risk.

WIAWSNB

Ta.

Well, I've gone for it - three 5.7kWh Alpha-Ess M48112-S batteries, and a Sofar ME3000SP.

Wish me luck…

QrizB

Good luck!

And please keep us informed of your progress, it's going to be an interesting project.

WIAWSNB

https://forums.moneysavingexpert.com/discussion/comment/81982714#Comment_81982714

Thank you - will do.

Thanks also for looking at the specs - I guess I can use these to manually set the Sofar, if it doesn't match one of the existing Alpha presets.

I was also reassured by you running a Sofar directly to battery with COMs, tho' obviously better if it has.

Is yours the same Sofar model, so 3kW max to/from the batteries? What size DC cable are you using, and where do you get your bits from?

Cheers.

QrizB

Is yours the same Sofar model, so 3kW max to/from the batteries? What size DC cable are you using, and where do you get your bits from?

Yes, a ME3000SP. I'm running fairly ancient firmware as I've never bothered to update it.

My DC cables are 16 sq. mm. which are rated for more than 100A and so should be fine for the max 60A that they'll ever see. I was previously using 4 sq.mm. solar cables and limiting myself to 30A in the Sofar settings.

You'll probably want some DC-rated breakers too, matched to the currents you expect to draw.

My bits are a hodgepodge of parts from Bimble Solar, eBay and (whispers) AliExpress ...

QrizB

It's a bit early to be taking about Sofar settings, but here's a set that might work for you if you can't get comms working.

1. Type: Default
2. Battery capacity: 336Ah (I think your batts are 112Ah each?)
3. Discharge depth: 80% EPS 90%
4. Max charge: 60A (or whatever you're wiring can cope with)
5. Over V protection 57.6V (3.6V/cell)
6. Max charge 53.6V (3.35v per cell)
7. Max discharge 60A (or whatever you're wiring can cope with)
8. Low V protection 46.4V (2.9V per cell)
9. Min discharge 49.6V (3.1V per cell)
10. Empty discharge 48V (3V per cell)
11. Full charge 56V (3.5V per cell)

This might make no sense right now but (unless your firmware is very different to mine) it will once you've got the inverter powered up.

I'm running essentially these settings with my Fogstar battery and it all seems to work ok.

(If there's anyone else here running a Sofar ME3000SP with 48V 16-cell LFP batteries and using the default battery type, I'd love to hear from you!)

WIAWSNB

Looking up the specs of the two types - the M48112-P(arallel) and S(eries) (which I have), the differences appear to be a slight difference in capacity, a higher nominal voltage, a higher overall operating voltage range, and a higher max charging and discharging current rate (which isn't going to exceed ~13A in any case).

Are these two sets of figures close enough for me to employ the Sofar's built-in parameters for the Alpha-Ess 'P' version, do you reckon? Or should I enter a fresh set of figures? I guess the slightly higher voltage range might compromise the performance of the 'S' if I restrict it to the P's settings?

Nearly there with the install. I've decided, since I may wish to move it all into the garage at some point if I get a WiFi CT clamp, to mount it on a moveable frame. If it all works ok, then I'll move the batteries to just outside the doors on the left, drilling through the PVC frame, and put them in a weatherproof unit out there.

QrizB

The "P" parameters look to me as though they're for a 15-cell battery, not a 16-cell one.

However, using the built-in "P" setting itogether wit an "S" battery is unlikely to damage anything.

I'd give the "P" setting a go and see how things work out. It should let you get everything up and running, at least.

WIAWSNB

Thanks.

The P settings also look to be 'safer' if anything.