I have been able to start equalization from the remote console using MultiPlus II → Advanced → Equalization, but now it doesn’t work anymore. No hw changes since I last used it, but multiple Venus OS upgrades and I have also installed the latest firmware in each Multiplus.
Read somewhere that it might not start if another unit is controlling the charge levels, which I don’t have. Tried the last Venus OS beta 3.70~7, but that didn’t change anything. It states “Starting…” but nothing more. If I leave the menu, and return to it, then the menu will not state “Starting…” anymore.
Does anyone have a clue what can be wrong? Any suggestions how I can troubleshot this?
What equalization does is to bring the voltage up to 3,65V per cell. Or more correct it targets 58,4V so that the bms can equalize the cells. (That is at least what I have understood it to do, and used it for). I normally start it, then after a short time I terminate it, which will give me the choice to enter absorption or float. (Then I select absorption to let the bms do its magic)
That is not what it is intended for. The BMS controls charge to keep the battery a suitable level for cell balancing which occurs in the upper end of charge.
3.65V, that is approaching the cell warning level for commercial batteries, is high and you risk the bms cutting off when the charger voltage exceeds the CVL it is sending.
Don’t equalise lithium batteries, it is a feature intended for old style lead batteries.
Configure your BMS correctly and then let it control charging. That is how the system is designed.
When servicing the batteries (newly installed or yaerly maintenance) it is nice to be able to force the chargers to fill upp the battery, and thereby get into absorption to fully balance. This might take more than an hour as I have set in the Multiplus.
I have not found a better way than to use the Equalizing-feature. I’m all ears if there is another way to do this
(flipping the switch charge-on-charge on the master Multiplus is supposed to do the same, but then I need to be at the location. And I don’t have the inverter model of the JK bms’es).
Why do you need to force a managed battery to charge and balance?
It is literally what the BMS is for, if it has been configured correctly.
You seem to be trying to fix a problem that should not exist on that chemistry.
Not sure how you ended up with that technique, but it isn’t standard. I will leave it at that.
I have a thought that before lithium profile was not checked and now it is in re-programming? As a lithium profile would not have equalisation as an option?
Sorry, but not sure how to do that, so the answer must be no. I have upgraded the MPII firmware to the latest version a couple of weeks ago (via Victron connect), and stayed on the official Venus OS version with automatically updates.
(Updating MP via VictronConnect requires me to load the configuration again to get the ESS assistant back).
On anycase absorption is the value you set for balancing and ‘equalisation’ in lithium batteries. Equalisation is where cells balance. And since you are using a jk bms that would be happening by itself as the bms is designed to self manage cell balance.
VictronConnect was only used for finding and installing the latest fw version. I normally use VeConfigure for setting up the unit, and yes I loaded a complete setup after update to get the assistant installed.
I will have a look at it asap. Thanks!
I’ve tried to find a up to date documentation for all settings, but haven’t found one yet. For example; Is there a potential problem in changing the setup using VictronConnect in a 3-phase setup, or is it totally ”safe” if the same change is made to all 3 inverters +++?
So I need to enable “use equalization” to make it work from the gui. That explained why I couldn’t start it. I don’t think that option exists within the VeConfigure software. Thanx LX for pointing this out!
Do you know another simple way to force the multi to fully charge the battery without flipping the swich on the unit itself?
Never had to use it with lithium so no, i haven’t tried.
The programming is almost the same, you just can’t use if for assistants like ESS.
I usually use VC for basic charger set up etc even in three phase. (Then ESS with ve config.)
Or as you did here.
I save a back up then resend it. (Then check it)
Yes. Set the absorption charger to the voltage required for ‘equalisation’. Then you can program length of time and repeat interval as well.
