Hello, the boat is equipped with a Lynx BSM NG + Lynx Distributor and a Victron NG 12.8 100Ah battery. We have connected the Lynx Distributor to the onboard battery. The boat has a charger for lead-acid batteries; is it sufficient to just adjust this charger to the values ABS 14.2 and FL 13.5, or does it require a new charger?
You could use this charger but
- The charger output would need connecting to the Lynx Distributor not direct to the battery. Just putting the absolute basic down, I doubt you would but just being cautious.
- It would not be controlled by the BMS target voltages via the GX and DVCC. The Lynx NG BMS charges at 14.0V with float at 13.5V.
- The only safety against overcharging or charging at high or low temperature would be the contactor, which isolates the complete system. If the charger has a remote on/off switch input then this could be connected to the ATC relay. If it does not have a remote on/off switch input then the charger positive output could be passed through a Victron Battery Protect or Smart Battery Protect to isolate the charger when charging needs to be stopped.
- Depending on how the charger determined the end of absorption and swapped to float you may have a longer absorption period than required. If the cells are balanced, the Lynx NG BMS swaps to float immediately, I usually see 3 minutes max. However if the cells need balancing, the Lynx NG BMS extends the absorption time, something that could not happen with an uncontrolled charger. I suggest if possible setting the absorption time to 10 minutes once balanced.
If I understand correctly, charging with the original boat charger could be possible if we prevent overcharging the battery. We will prevent overcharging by placing a Smart Battery Protect on the bow pole, which will be controlled by a BMS.
The above is correct.