300 Sundancer converter

[NicelyDunnII]

My 2006 Sundancer 300 has two sets of two batteries. One set starts the port engine, the other set starts starboard engine. After leaving the boat unused for a week or more with shore power connected and converter on, I have had two occations where the startboard engine batteries were dead and would not start the engine. However, after getting it started with the crossover switch and running the boat, the starboard batteries seemed to be charged and next time turned the engine nicely.
My question is this, is the conver connected to both sets of batteries or just one set? I thought that if it were connected to both sets the then all the batteries would essentially be connected together. If only connected to one set, it would explain why the starboard batteries go dead at the dock but not the port batteries.

 

[cfd95]

The charger should charge both banks of batteries.
When was the last time the batteries were replaced?
If they are bad a charger is not going to keep them up to proper voltage.
IF you shut the battery switches off when you leave the boat there should be nothing drawing them down.
If 1 battery is bad in the bank it will draw the other battery down.
You need to have the batteries tested and verify with a multimeter that the batteries are charging when the charger is on.

 

[JimG]

cfd95 provided spot on comments... just a couple more to add...

The dual charger outputs are isolated so your batteries are not connected together. Your E-start feature connects them directly together.
Also, check your battery terminal connections.

 

[JVM225]

The charger should charge both banks of batteries.
When was the last time the batteries were replaced?
If they are bad a charger is not going to keep them up to proper voltage.
IF you shut the battery switches off when you leave the boat there should be nothing drawing them down.
If 1 battery is bad in the bank it will draw the other battery down.
You need to have the batteries tested and verify with a multimeter that the batteries are charging when the charger is on.

Solid advice!