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Customize equalisation settings for batteries

Regarding equalisation of flooded lead acid batteries, taken from Victron manual:

This setting is intended for flooded tubular plate traction or OPzS batteries. During absorption the voltage limit increases to 2,83V/cell (34V for a 24V battery) once the charge current has tapered down to less than 10% of the set maximum current. Not adjustable with DIP switches. See ’tubular plate traction battery charge curve’ in VEConfigure.


I'm wondering if there will be an issue here. To equalise our batteries (to get in the 31 - 33v range as specified by manufacturer) equalisation charging current is usually around 50 - 55A, due to the size of our battery bank (1380AH). So I'm wondering if this will allow correct EQ charging. If it tries to equalise 10% of charger capacity (70A) being 7A it won't work. Or does it refer to 10% of battery max charge current, which is much higher than the 70 amps this inverter can do. Are EQ settings customisable or am I misinterpreting it?

Note that under all other circumstances 70a for charging is more than enough, its much more than they get from the sun the other 9 months of the year.


Specs from the battery manufacturer are as follows:

Equalisation current: 3.5% of C100 AH capacity (1380AH) gives us 48.3A. That sounds about right.

Should give voltage of 2.6 - 2.75 volts per cell (31.2 - 33v), thats about right, maybe at the lower end of the spectrum.

Interval: 20 days.

Duration: 2 hours.


They really do seem to need it at least once a month during winter, even with conservative DOD. I've attached documentation should you wish to view. Also note normal recharge maximum voltage should be 2.45v per cell, I believe that means absorption should be set to 29.4 volts. That was definitely the case with the PWM charge controller we inherited with the system.


So how to get multi to equilise correctly!

MultiPlus Quattro Inverter Chargerbatterymultigridequalisation
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