Carver Owners Forum

Still trying to fully understand DC electrical system on new to us 560 Voyager.
It's my understanding that the 12V house batteries are not charged by the 24V engine electrical system. Thus, we must run the generator to charge house batteries while at sea. This to avoid deep discharge of house batteries from inverter run fridge and freezer. Do I have this right?
It seems like we could install a 24V to 12V transformer (some online retailers call it a converter) so the house batteries are charged when underway. The transformer would need to be disconnected when we are at rest (no shore power). Maybe there are transformers that are smart enough to disconnect when 24V system not getting charged.
TIA for your thoughts and advice!

Unless there has been a modification to your system, the port engine has 2 alternators and is responsible for charging the house batteries while running. I have the same boat/year and that is the way my is designed.

Thanks for heads up on port engine. I'll investigate. Also have a mechanic coming this week, so I'll get his advice.

A Lee -- you are, of course, right that port engine has 12V alternator for house batteries. The survey mechanic threw us on track telling us house had to be charged by genny under way, which made NO sense.
Progress on fixing rear bildge pump float switch and replacing owner's state room shower pump. Yay!

The fuse for the 12v ALTINATOR is on the firewall behind the starboard engine and hard to see.

Trixboat wrote:Source of the post Still trying to fully understand DC electrical system on new to us 560 Voyager.
It's my understanding that the 12V house batteries are not charged by the 24V engine electrical system. Thus, we must run the generator to charge house batteries while at sea. This to avoid deep discharge of house batteries from inverter run fridge and freezer. Do I have this right?
It seems like we could install a 24V to 12V transformer (some online retailers call it a converter) so the house batteries are charged when underway. The transformer would need to be disconnected when we are at rest (no shore power). Maybe there are transformers that are smart enough to disconnect when 24V system not getting charged.
TIA for your thoughts and advice!

Sounds like you got the issue figured out, but to follow up on the second part of your post in case others might be interested.

What you're referring to is a "DC-to-DC charger", not a transformer. There are several available and can have different input voltages and different output voltages. You can get a 24V to 12V one and they also have provisions to shut off if the input drops to a specified amount (so that you never drain down the source if it's not being recharged).

The Port engine has a 12 volt alternator to charge the house batteries. Took me 60 days to figure this out as this does not show up in the wiring diagrams and Carver didn't mention it in the system description. So to recap, there is a 24 and 12 volt alternator on the port and 1 24volt alternator on the starboard for a total of 3 alternators.

Hello Everyone

I apologize in advance if this question was already answered, but I am relatively new to the Carver world and would like to get some advice on a couple of topics (I have a 2005 Carver Marine 36)

1) - When I'm at the dock connected to shore power, obviously all of the electrical systems work, however, when I disconnect the shore power, all of the electrical (12v system etc) will turn off and the dead battery alarm will go off and will not come back on until I start the engines...But if I turn off of the engines (with no shore power), the 12v system will shut off again. .....As an example, if I am out on the water, drop the anchor, turn off the engines, I will not have access to the radio etc...I realize the generator is an option, but I figured the 12v system would run off the battery when the engines are not running, or is the generator the only option? What are your thoughts?

2) - when connected to shore power at the dock, is it necessary to have the compressor come on from time to time or is there a way to turn it off at night?....it can be loud in the middle of the night.

Thank you in advance for helping me out.

This was a reply to brow_14 : (for future reference, you should start a new thread for a new problem so it doesn't get confused with the other issues)

Sounds like you might have a bad house battery. If the engine(s) start just fine, then those batteries might be OK, but with the engines running or the shore power available, there is power getting to your house battery which would supply power to all those electric systems. I would check the house battery. It's possible there are just corroded connections to it, or it may be dry (if a conventional lead-acid battery), but I would bet you'll end up replacing it. Any idea how old it is?

for #2, which compressor are you talking about... the HVAC? Are you sure it's a compressor you're hearing? Do you have vacu-flush systems? Do you have actual air horns or electric "air" horns? (the real "air" horns also use a compressor)

Thank you km1125

- I don't know how old the batteries are, I just bought the boat and had a mechanic inspection and survey done with no reported issues on the batteries (doesn't mean they didn't catch it)..., but I will check the house battery- Thank you!
is that to say that the house battery will be charged by the shore power as well?....or does the house battery get charged by the generator?

- to answer your question on the compressor, I believe it is the horn compressor ...can that we switched off (at night)?