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Hi
just reading the operational manual, would it be possibel inside a 3xMP2 5k ESS System with BMS on 54,4V (Pace BMS Pack Volatge) to run a higher voltage as 55,2V to start the active Helllltec Balancer (3,45V) ?
Just to automize the balancing process every week...
Did anybody use that for his LifePO4 packs?
If its a managed battery DVCC is likely forced on and the BMS will set the limits for all chargers.
If you disconnect the battery BMS and disable DVCC, then you can set voltages manually.
Balancers are not normally used with lithium batteries. The BMS is unlikely to enjoy a higher voltage, Pace already likes to send high voltage alarms.
Balancers are only seen sometimes if someone tries to connect batteries in series. Where vendors support this, their BMS is usually capable of dealing with this layout and don't need external help.
Why are you trying to do this?
@nickdb has explained it nicely. With your approach, what happens when the BMS decides no charge to the battery? If you must do it, you have to disable the BMS or change its parameters. Neither is recommended.
F
that means it is not possible to use this function
of course LifePO4 needs Balancer, not all time and not during daily use, just to take care of the capacity differences in cells.
therefore I wanted to use it, but so I need to do it via DVCC again.
as I wrote the Gobel has the Helltec 4A active installed.
Unless you can program the bms to allow the higher charge or the heltec to start balancing much sooner, there is no way the two can work together.
F.
You have incompatibility issues.
Change the design and components choice.
Hi @4711Austria
I see that you are pretty determined to do it your way... :-))
In that light, even if there are some protections in place, anything can be done.
MPPT 450/100 is just a worker and it does what it is told. So, you just need to use a Cerbo or similar and to modify some scripts inside the Cerbo's OS.
What you are looking for is the script dvcc.py from the /opt/victronenergy/dbus-systemcalc-py/delegates folder.
See that there is a function inside named _adjust_battery_operational_limits() which process various quirks of some batteries. You can introduce your own logic there and rise accordingly the float voltage and charging current limit as you need.
Alex
Just wanted to ask here, if the function inside the MPPT would do a job for me, but unfortunately not.
Special systems have special problems and that is usually followed by an unhappy user blaming the product.
Moving to modifications as this has gone off piste and will have gone off support as well.
Second that!
It's a "do it at your own risk" thing and be very careful with what you are doing as you can damage things...
