Suggestions for settings?

[Aphers]

Six months in I am fine tuning my system. I have a JBD BMS, and an Epever Tracer MPPT.
When I first set it all up, the BMS would cut out at full charge, which I understand is bad for the MPPT as it no longer has anywhere to sent the power.
I appear to have got away with this but I was generally careful to watch the SOC and manually intervene.
I have now tweaked the settings on the MPPT, so that it stops charging earlier. But I haven't got the balance right. The battery can dip down to <50% SOC before it starts charging again. I know this isn't doing the system any harm but I want to be getting the battery back to full, or I will run out in the evenings.

Any suggestions for what settings to use? Thanks

 

[time2roll]

I would start with 13.8 charge and 13.5 float to see what goes.
Although generally I would expect the battery to support the load for 24+ hours in normal conditions. So once full per day should always get through the night. May need more battery.

 

[Aphers]

The settings just now are:
BMS: 3.65/2.9v over/under volt; 14.6/11.8v pack; 3.4v balance start
MPPT: 14.1v over-volt disconnect; 14v charge limit; float charge 13.2v

Maybe I should increase the float charge, I will try 13.5v.
I would like a bigger battery but not really likely just now- I'm now living on the boat full time and can't really stop somewhere for two months to wait on cells arriving.

 

[Browneye]

I have the same setup - 230A battery. I'm still using the same default bms safety settings/limits.

How does your cell balance look at the top of your charge? I tend to get one or two cells that will run if I try to push the pack to 3.6V/cell. So I have actively balanced them (bleed off) to keep them even at 3.45-3.55V/cell, and my boost voltage to 14.0. That way I don't have one or two cells reaching full charge early and shooting over the bms limit and it shutting down charging.

13.5 to 13.6 is good for servicing a load. Your pack voltage is going to settle when charging stops. I just would not leave them there long term, like for storage. For that I like 13.35V - the pack will tend to settle back to about 70% and stay there till the next boost which gets them back to about 98-99%..

If boost starts when the sun comes up you should reach full charge as the controller drops to float - and should then service your loads until dusk.
If you have enough capacity, you can float lower with a higher boost-reconnect so your panels charge it back up.