Skag
Veteran Member
- Joined
- Mar 25, 2021
- Messages
- 41
- Vessel Name
- Chrysalis
- Vessel Make
- 2006 Metal Craft Marine 50' Trawler
Last time I used my thruster, it was weak and didn't make much noise like it used to. I found that the two group 31 AGM's in series providing 24V to the thruster were near dead. I have since traced down the wiring and found the two thruster batteries are connected to my group 27 flooded lead acid (FLA) starting batteries (also in series 24V) through an ACR. When at the dock, the FLA starting batteries are charged by a small two bank 20amp 12V charger and the ACR closes to charge the thruster AGM's. When underway my 24V/35amp alternator charges the start batteries and the ACR closes to charge the thruster AGM's. I suspect I may have damaged the AGM's by combining them with the FLA batteries - likely overcharging them?
Curious how others may have their thruster battery system arranged (type of batts, charging at dock, charging underway).
At this point, I need at least two thruster batteries, but am contemplating just going with lead acid to match the start bank as I think that would solve the potential damage issue (too high of charge voltage from the FLA charger). I'd prefer AGM as I would rather not have the acid/maintenance. Should I go with 4 new AGM's (thruster and engine start)? Or just buy lead acid for the thruster and call it done. If going AGM for both start and thruster, would I need an external voltage regulator for my 24V 35amp alternator? Reading through several posts I see that you can damage an AGM battery if charged as a FLA battery. Would a DC to DC charge controller solve the mismatch?
I also have a 600 AH of AGM's for my 12V house bank that when underway are charged from my Delco 22SI 145A alternator - wondering if i should proactively convert to external smart regulator.
Curious how others may have their thruster battery system arranged (type of batts, charging at dock, charging underway).
At this point, I need at least two thruster batteries, but am contemplating just going with lead acid to match the start bank as I think that would solve the potential damage issue (too high of charge voltage from the FLA charger). I'd prefer AGM as I would rather not have the acid/maintenance. Should I go with 4 new AGM's (thruster and engine start)? Or just buy lead acid for the thruster and call it done. If going AGM for both start and thruster, would I need an external voltage regulator for my 24V 35amp alternator? Reading through several posts I see that you can damage an AGM battery if charged as a FLA battery. Would a DC to DC charge controller solve the mismatch?
I also have a 600 AH of AGM's for my 12V house bank that when underway are charged from my Delco 22SI 145A alternator - wondering if i should proactively convert to external smart regulator.
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