Energy Matters Forums

[angusjones8]

Got onto EV works and bought 16x BMS-CBM400 balancers, BCU-RAPS-16c battery control unit and a CHG-A-16C25A charger.
Think all I need now is a decent fuse disconnect and some cable.


What sort of baseline settings should I start with on the FM80?

I also rang Latronics about increasing the LVD and they said it's a bit of a major, he said it can be done but it will raise the HVD (I think) by 3 volts.

Should start putting things together in a week or 2.

[Gordon-Loomberah]

I had mine modded before it left the factory, to 49V, although the only time it has been activated, from memory I think it was a bit under 48V.
I'd suggest Vabsorb of 55V, and Vfloat 53.5V, and you'll need to work out your absorb time by watching net charging current, and it will depend on how fully charged you want to take the battery.
If you need to get the battery charged faster, then a higher Vabsorb will work better, but I wouldn't go over 56V for an extended period, particularly in summer.

Use a good quality multimeter to check your voltage set points, don't rely on the FM80's display.

[angusjones8]

Thanks heaps for that.
I want to be kind to the batteries so I'll keep on the safe side.
I got a new fluke multimeter coming, my old $9 is on its last legs.
Sounds like a few weeks of monitoring is in order which sound like fun.

[angusjones8]

Well I'm all up and running!
I only have 3.2kw of panels wired up so far and it's plenty enough.
I find I'm drawing the battery down more than I would have liked over night but it seems to be only charging up to 53.2v every day so this could be an issue I need to look at.
During the day I have more power than I know what to do with and I still have 6 more panels to wire up, I think I'll put them on the western side of the roof for some afternoon sun.
I'd like to tidy up the DC side of the wiring a bit but that can wait.

[Gordon-Loomberah]

...it seems to be only charging up to 53.2v every day so this could be an issue I need to look at.

Absorb voltage set too low? You wont get near fully charged at that voltage at this time of year- the days are not long enough.

[angusjones8]

My absorb voltage is 55v I think and the BMS says 100%.
I'll do a bit more research on the bms side.

[angusjones8]

Just an update. Have been living with my system for 4 months and everything is going great. We use more power now than when we were on the grid and I'm loving every minute of it!

[Gordon-Loomberah]

Good news

Did you put the extra panels on the W roof?

[angusjones8]

Yeh I did so now have 18. Prob don't need them but got sick if tripping over them!
Thank you so much for all your help!

[angusjones8]

Just read it properly. I ended up putting 3 panels on the western side of the roof, we use a bit of power in the arvo cooking tea ect so it probably helps a little.
It's amazing how little light is required to start making power in the mornings and on overcast days. We had a long weekend where it rained for 4 days and we were fine.