Charging HP AGM Batteries

[nahfloors]

I just bought two Vmax SLR 125s for the trolling motor. My starting battery is a Everstart group 31. My charger is a Pro Mariner Prosport 20 plus. I need to switch the programming cap over to High Performance AGM, but Im assuming this will affect how my Wet Cell gets charged. My question is: Do I need to switch the starting battery over to a High Perfomarnce AGM too?

I was hoping I could program each bank separately, but it seems not to be the case.

[Lightning1]

According to this the min charging current for that battery is 8 amps. The 3 bank charger puts out 3x - 6 amps. Not really answering your question but are you sure that is the right charger for your application? Sorry if this isn’t a hot link.

https://www.vmaxtanks.com/SLR125-12V...tery_p_38.html

[nahfloors]

good point. Ill call ProMariner and Vmax this week and get their take. I would assume if the ProSport 20 plus is setup to charge High Performance AGM batteries it would be fine, but maybe not.

[Lightning1]

FYI the 6/6/6 I read in the manual was cable length, not current rating. Sorry I misread and good luck.

[DW]

When you switch to the AGM the charger will deliver less voltage. The wet cell will charge but at a slower rate. I would try it and after charging test the wet cell voltage and see if it is fully charged. After letting it rest overnight it should measure 12.6v.

[mikear]

I would definitely call ProMariner. Their manual states that the voltage is higher during both Absorption and Float for HP AGM vs. Flooded lead acid / standard AGM. HP AGM is 14.7V Absorption and 13.6V Float vs. 14.6V/13.4V on flooded / standard AGM. Therefore, if all three banks are charging with the same HP AGM profile, your cranking battery will be receiving a higher voltage than intended and may lead to gassing.

https://images.platforum.cloud/uploa...6e33553d6a.jpg

[nahfloors]

After talking to ProMariner, it turns out the 2 bank charger has the HP AGM cap but the 3 bank does not. But he said I can just leave it on the standard Lead acid/AGM setting and Ill be fine. I intend to get a AGM starting battery anyways and likely will upgrade the charger soon too Although Vmax said that my charging specs were fine.