svviolethour avatar image
svviolethour asked

Solar MPPT equalization stops prematurely

I've read the manual and similar community posts on this but haven't been able to determine the answers to these questions.

1) The manual and faq say equalization times out at (absorption time / 8) or (absorption time / 2) for a custom battery type. Is "absorption time" the "max absorption time" that I have configured in the MPPT settings (9 hours) or is it just the absorption time that the controller ran absorption cycle for on that particular day? (typically 1.5 hours, since I don't deep discharge the batteries at night)

If it's the latter (absorption time on this particular day), that's pretty odd because equalization on lead acid batteries typically needs to run for 4+ hours, and the time required shouldn't be related to an arbitrary factor like what voltage the batteries started at that day.

2) The manual/faq also say equalization will stop if the controller current goes above 25% of the bulk current (for lead acid batteries). With a 75/15 controller, that's .25*15 = 3.75A. Does this mean if my refrigerator turns on (this is a solar setup on a boat), the equalization will stop? (the fridge draws about 7A, so it will appear that the charging current is above 3.75A although really it's not, because the 7A is going into the fridge load).

If equalization is interrupted for this reason, does it restart once the load goes away or does it give up for the rest of the day?

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

1 Answer
svviolethour avatar image
svviolethour answered ·

Can anyone at Victron help with this? I emailed Victron sales (only email I could find) and they said to contact the reseller, and I did so (an Amazon reseller) but they never replied. I doubt they know the technical specifications of Victron products anyway. Does Victron really not support their products anymore? I bought Victron solar controllers because the product support a couple years ago (through email and blog comments) seemed quite good. Now I'm having doubts.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Related Resources

Additional resources still need to be added for this topic