Lagoon 340 -88 Battery charger

[Sitruuna]

How I can charge boats batteries when it is on ground power? Should I do anything else than put the power on or how the switches should be? I wondering is the problem on batteries or charger? Where the charger locate?

[Salty]

Welcome to the forum.

When I bought my B36(2002), the battery charger had no separate on/off switch. Whenever connected to shore power, and with the mains isolater switch on the control panel switched to on, the charger was connected and the batteries were being charged whether they needed it or not. This was however subject to any automatic sensing system that may have been provided within the battery charger itself. The charger has a 220 volt power input light, and this always, and still does show when connected to such supply. A consequence of having continuous charging was that if the charge sensor had some kind of malfunction, it was possible to over cook the batteries. So to retain some kind of control, I fitted an illuminated rocker switch to the 220 volt supply panel to enable me to switch off the battery charger if, in my opinion, the batteries did not need further charging, and with the light it emitted to remind me whenever the charger was switched on.
On my boat the mains battery charger is located under the chart desk, though it is perfectly possible for it to be located elsewhere on your Lagoon, so unless someone else knows where they are located then you should roll up your sleeves and start looking. I suggest you start at the batteries, find the charging leads (small wires), and follow them until you find the charger, if there is one fitted.
You didn't mention what you think the problem is, so I'm guessing that your batteries are discharged and they do not charge while connected to shore power. Do they charge up when the engine is running?
A temporary work around might be to bring an ordinary car battery charger to the boat and to plug it in to a mains socket and connect the leads to the terminals on one of the batteries and see whether that makes any difference. If it does, the next thing will be to see how long it takes for the charge within the battery to run down. It may be that the batteries onboard are exhausted and need to be changed for new ones, but don't spend out on new batteries until you have determined whether you have a mains charging system fitted on your boat.
Good luck, and get someone to help you tracing the wires, very handy when wires pass through a bulkhead along with a multitude of others.

[Sitruuna]

Thanks for help. Charger works, fault in batteries.

Where can I get Lagoon's manual?

[Symphony]

Your boat comes from a time when owners manualls were not compulsory so what was provided was minimal. Also you find with older boats that some equipment has been changed or replaced so not the same as original. You can try the Bavaria factory as they seem to have files of manuals going back about 20 years, but your boat is a very different design and built by a different set of people!

[Salty]

Thanks for help. Charger works, fault in batteries.

Where can I get Lagoon's manual?

Don't be too quick to blame the batteries, it might be that a previous owner has had some extra electrical item fitted which has been connected directly to the batteries, and which is not getting switched off when you leave your boat. In consequence your batteries may be getting discharged at a time when you think everything has been shut down. Again, look at the batteries and determine what each of the wires connected to them does. In particular look at any small or large wires connected directly to the batteries that do not go through your main battery switch or switches.

[Sitruuna]

The boat has not been used for 5 years. The batteries are old and have not been used. I put new batteries, and now it works.