Need some assistance with my battery...

[ajb]

Need some assistance with my battery that supplies the power to start my generator . Aside the normal hook up neg and pos terminal I have a red, assume hot, wire that is attached to the pos terminal. Is that the wire coming from my AC converter to charge this battery? I have used a meter to see if this wire has power to it but not getting a reading.

Thanks in Advance

[wingless]

Chances are that extra wires on the battery terminals have been added after the boat was built.

That 2001 340DA was built by Sea Ray according to ABYC standard, applicable at the time of construction.

One of those standard limits the quantity of wires on each battery terminal, I think three is the max.

On my 2000 380DA the factory put two max on those terminals. That was to permit daisychaining battery wiring.

My strong suspicion is that the factory wired the on board battery charger to the terminal lug at the battery disconnect. It is electrically identical to the battery AND satisfies the ABYC limitation.

[ajb]

thank you for the info, yes two wires to the pos terminal, anyway to tell if this is charging the battery?

[wingless]

The thick wire is for the engine and house or helm power.

The smaller wire is something else.

The "easy" way is to properly disconnect the wire for diagnostics.

First disconnect shore power. Then carefully disconnect the battery negative terminals from all batteries, securing and insulating each. Lastly disconnect and insulate the thinner wire from the battery positive terminal.

Then carefully reconnect each battery negative terminal. Reconnect shore power.

With the charger powered measure the voltage on that wire relative to battery negative.

If it has battery voltage then toggle off the battery charger to determine if it is the battery charger output.

If it doesn't have voltage, then determine which device on the boat is no longer powered.

[J-Rod]

It might be your bilge pump that needs power when the battery switch is turned off.

[wingless]

@Gerard O'Connell, welcome to the forum.

Interesting observation.

The factory would not have wired the fused OEM bilge pump wire to the battery, even though it requires unswitched power.

They instead connect that unswitched fused feed to the battery side of the main battery disconnect switch.

It is electrically identical and provides a much cleaner / easier installation.