Batteries not charging while underway. PDQ34

[Brewster]

Hello all,

Bruce on B-Side (hull 102)

We’ve been cruising the Great Loop and just completed this month. We have a month or so before we head out again to do the Keys and Bahamas.

During cruises of 4 hours or longer, the chart plotter is indicating that battery voltage is low, 11.8v and declining. Since we were cruising, I simply used the generator underway to solve. As we ready for the Keys and Bahamas, I’d like to resolve!

Did a bit of reading on the forum and understand that the combiner (xantrex 250) may be the issue.

When connected to shore power, all batteries recharge through Victron Multi Plus Compact charger/inverter. The combiner has yellow light, as expected.

When starting engines and underway, it remains yellow (disconnected). It should be connected.

Suggestions to further troubleshoot?

Thanks, Bruce on B-Side

[duetto]

hi,

combiner should be green even when shore power/charger is working. the combiner has a switch which puts it in disconnect mode. i would check that. if that is in correct position, there are rotary dials on the left facing the combiner. these control shutoff voltage amongst other things. make sure you don't have it set to high. lastly, if all this proves ok, i'd check the "solenoids". we had a case where they pitted and would allow charge current to pas, BUT the green light was on, so this is probably not your problem.

good luck, when you solve it post a recap.

[Brewster]

Didn’t realize that the switch was 3 position.

With shore power off and engines off, moved switch from left to center. The indicator turned green. Then a few minutes later it popped (switch triggered) and yellow light is now on.

Reconnected shore power. It switch on to green again. Disconnected shore, yellow. Engines on, green!

I believe it is working properly. Anything else I should check?

Thanks!

[duetto]

i think that you're good to go!

[deising]

Bruce,

Just in case you or anyone is not familiar with the battery combiner, it is designed to use the solenoid switches to connect the 3 battery "banks." In our case, the house bank and the two engine start batteries. It connects (light goes green) whenever it senses a voltage higher than the set amount (13.0V is our setting, I believe). While 13.0V is not nearly enough for an effective charge, it indicates some sort of charging source available.

When disconnected from shore power, the start of either engine with a functioning alternator should cause the combiner to connect. This will recharge the house bank when you are moving for long enough. Idle speeds do not provide much from the alternator, obviously.

Similarly, when the there is a charging voltage from a solar panel array/controller, the shore power or the generator through the inverter/charger, the combiner will connect to also charge the engine batteries.

The generator battery is not connected, by the way. That is one good reason to start and use your generator (under load) on a regular basis. The generator's alternator recharges its own battery and nothing else.

You can manually connect the 3 banks with the combiner switch if needed. That might the case if your start battery is weak (replace it soon!) and you use the fully-charged house bank to get you going. Of course, if only one engine battery is weak, start the other engine first and the alternator will connect the combiner for you.