39: Need battery info

[Marjane]

Which battery or batteries power the electric winch and which powers the windless…am having trouble figuring that out.

[Pete7]

Every boat is different. You will have to follow the wiring back to the batteries which can be in the bow area, or wires run all the back to the engine/house banks.

[jen1722terry]

I agree with Pete7, you'll have to trace the cables from the batteries to the winch and windlass.

Fortunately, these cables will will be much thicker that most other wiring in a boat. So you should be able to trace them fairly easily.

Dumb question: is there a battery forward to serve the windlass? Some boats have these to eliminate the need for very long battery cable, which decreases the ammount of electricity getting to the appliace (winch or windlass).

Best of luck

[Peeew]

Perhaps the manufacturer can supply a wiring diagram? Depends on who built it but many will have them.

[Pandor]

You’ve got multiple battery banks, right. They are controlled by one or more battery switches that allow isolating each battery bank.

What happens when you isolate one and try the winches? Then isolate the other. Keep going for the number of banks/switches. If they are powered by more than one bank, the banks are paralleled somewhere.

[smac999]

Stock an amp clamp meter on each bank 1 at a time and run them. You’ll find out.

[Marjane]

Thanks, good suggestion. Turned off domestic battery bank and winch does not run…assume windless it powered by port engine battery as per many lagoons. Just trying to figure why our new Quick windless has slowed down….we switched batteries with the generator battery but still slow🤪

[TrentePieds]

It's doubtful that your particular installation conforms to any standard. Even if it did when new, it may have been altered.

From the motor on the capstan/winch there will likely be two fattish, black wires going to a magic box. That box is a "reversing relay". From it there will be two fattish, black wires, or perhaps one red and one black that lead from the reversing relay to a battery somewhere. That battery is the one the drives the capstan/winch.

From the relay box there will also be skinny wires leading to the "control position", whether that be foot operated push switches ("normally OFF" type) mounted in the deck adjacent to the capstan/winch or hand operated push switches ("normally OFF" type) at the steering position.

Because capstans/winches draw a LOT of juice, ALL connexions ANYWHERE in the circuits need to be scrupulously clean and solid. Else the capstan/winch motor will slow down or not operate at all. So do a preventive maintenance tidy!

Note also that while a multimeter placed on the battery terminals may well show "full charge", at the end of a long battery run (if you have say 20 feet from battery to capstan the "run" is twice that i.e. 40 feet) the measured voltage at the capstan when at rest may show "nearly full charge" but when you OPERATE the capstan the voltage may drop below the minimum required by the capstan motor. In such a case the multimeter across the battery terminals will drop precipitously when you operate the capstan. That indicates that the battery has had the biscuit and needs renewing.

If you have a separate battery near the capstan, make sure that the voltage measured at its terminals is at the "charge level" for a battery of the particular chemistry. If it is below requirements, check, tidy and repair the wires that run twixt that battery and the alternator and/or battery charger.

TrentePieds

[Tin Tin]

Lagoon windlasses are not necessarily powered by the port engine start battery. The Windlass contactor/solenoid/relay on-off is powered by the port engine ignition system, this is a smallish wire with a small fuse. The Contactor then feeds the main power from thick cable into the windlass motor. These cables are likely connected to the house bank via breakers (something like 60-100A), usually near the battery.
Similar contactor set up with the sheet winch, except it is triggered by the button switch.


The generator start battery system may be a bit small to power the windlass. It will need thick cables/jumper leads connected to the windlass contactor. The Quick owners manual will show the wiring diagram.

Is your boat a Lagoon- what model? If so it likely has a wiring diagram.

If your windlass is slow with engines and or generator running then there is a good chance the cabling is inadequate/ corroded or loose terminal somewhere (or the electric motor brushes on the Quick need replacement and a clean out of carbon buildup, would need to be a couple of years old, you say it is new.)

[SV Confianza]

Do you have a battery monitor? When running the winch, look for the bank that has a voltage drop. They pull a good amount of juice so, so you should be able to see the voltage drop on the bank that it’s connected to.

[Bowdrie]

It ain't rocket science.
Disconnect the batteries, connect them up one at a time, see which one makes the windlass run.

[Marjane]

When you are a 76 year old lady it feels like ROCKET SCIENCE 😂

[Bowdrie]

Originally Posted by Marjane

When you are a 76 year old lady it feels like ROCKET SCIENCE 😂

Sorry, no harm intended.
Yes, I know that sometimes wiring and cables get packed away and stuffed behind all kinds of interior furnishings in such a way as to make tracing them near to impossible.
That's when we have to do things by process of elimination.

[donradcliffe]

The fact that the windlass is new might be a clue. It may not be a battery problem, but a connection problem.

I assume in a French boat, you may not turn on the windlass unless either the port or starboard engine is running (which I consider to be a really bad idea) If its alternator is functioning, the voltage across the positive and negative posts of the nearest battery is expected to be somewhere around 13.5-14 volts. Keep measuring the voltage as you turn on the windlass. If it drops to 12-13 volts, that is normal. If it drops below 10v, you probably have a battery problem.

Now go to the windlass and measure across the cables going into the windlass when you turn it on. There could likely be three thick cables going into the windlass, one for power up, one for power down, and one for ground. Measure the voltage across the terminal to the ground wire and the power side which is energized when you turn the windlass on. If the voltage is less than 9 volts, you have bad wire connection(s).

Now take a long wire back to the ground post of the battery, and measure the voltage under load between (1) the energized hot wire at windlass to the battery ground and (2) the windlass ground to the battery ground when the windlass is running. This will usually tell whether the wiring problem is on the ground side or the positive side.

[Marjane]

Turns out to be a voltage drop overnight. Remedy: we run the generator with battery charger 20 minutes before using the windless and electric wench. Problem solved! Thanks all for the imput!