Lead acid battery MPPT solar controller settings

catlotion

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I've searched long and hard for a clear answer to this but struggling a bit.

I've got a Victron 100/20 MPPT controller for my 260w solar array. I'm also just about to fit 3 X Exide ER550 lead acid batteries and want to ensure I've got the right charging profile setup. The datasheet from Exide isn't any help and they don't reply to my emails. I've set it up for now with the values attached (think float voltage is a bit high) but I want to get it right when I fit the new batteries. I got the batteries from Tayna and they repled with the attached but absorption sounds really high at 16.2v?

I'm thinking of using 14.4v for absorption voltage and 13.2v for float. I understand that equalisation should be disabled so that setting is irrelevant? Also setting temperature compensation to following: -30mV/°C, absorption duration fixed, absorption time 3 hours, 4A tail current...

Thought this would be fairly simple! And that there would be a generic lead acid profile in the MPPT controller (there are only gel and LIPO)
 

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I'm sure that's a mistake, 16-odd volts would be equalisation.

The other values look sensible enough, but you should not just consider the voltages, but also how the Victron decides how much absorption is needed every day. These things tend to default to settings which are intended for sytems where there is a significant load every night, which can result in overcharging on a boat only used at weekends for instance.
 
The default user defined value is for regular lead acid batteries ie. 14.4v absorption, 13.8v float and 16.2 equalisation. I only tend to use the boat at weekends so have disabled the equalisation and used 13.4v for the float
 
I've searched long and hard for a clear answer to this but struggling a bit.

I've got a Victron 100/20 MPPT controller for my 260w solar array. I'm also just about to fit 3 X Exide ER550 lead acid batteries and want to ensure I've got the right charging profile setup. The datasheet from Exide isn't any help and they don't reply to my emails. I've set it up for now with the values attached (think float voltage is a bit high) but I want to get it right when I fit the new batteries. I got the batteries from Tayna and they repled with the attached but absorption sounds really high at 16.2v?

I'm thinking of using 14.4v for absorption voltage and 13.2v for float. I understand that equalisation should be disabled so that setting is irrelevant? Also setting temperature compensation to following: -30mV/°C, absorption duration fixed, absorption time 3 hours, 4A tail current...

Thought this would be fairly simple! And that there would be a generic lead acid profile in the MPPT controller (there are only gel and LIPO)

I wouldn't use the Tayna float setting (it is, as you suspect, too high for SLA batteries), or your 13.2v for float (it's a bit low). I would use 14.4v absorption and 13.6 float. As others have said, the 16.2v absorption is an error, that's the equalisation voltage, which you wouldn't use with sealed batteries.
 
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