Blue Sea Add a Battery Issues

[TDudley]

Can some one help me with an issue resolving where to hook my Alternator when using the Blue Sea Add a Battery system.

Blue Sea give the user the choice of connecting the Alternator to either 1. the starting Battery, 2. the house Battery, 3. the battery engine side of the battery switch, or 4. the starter it self.

I chose to hook the alternator to the starting battery. But I think this ends up bypassing the switch which in turn allows the motor to be in the starting mode even though the switch is in the off position.

Has anyone done this and if so, where did they take the alternator hook up. I am now leaning towards the Battery Switch. A picture of the system is shown below. Thanks,

 

[sailaway78]

Starter

If you are describing what I think you are, I would attach the alternator output to the battery terminal at the starter. This will allow it to go through the selector switch, and makes for the shortest wire run of any method. And you can charge either bank or both at your discretion.

 

[tommays]

I do believe the alt should go to the ACR which would then charge the starting battery and when full switch to the house battery


There switch allows the house and start to be on BUT not run each other down and then combine as a last resort

 

[Ed Schenck]

Page four of the installation instructions( http://bluesea.com/files/resources/instructions/990170140.pdf ) states that the alternator can be connected to any of the aforementioned. So I think it should be unchanged from where it was connected originally. On my boat that would be the starter post.

 

[Maine Sail]

Running a new wire from the alternator directly to the house bank with a fuse at the battery end is the method I prefer. It allows for excellent voltage sensing, provided your wire is sized correctly, and also prevents you from every frying the diodes in the alternator as the alt will always see the house load. For working on the engine you simply pull the fuse to break the alt wire.

I have found that wiring directly to the start battery can cause the relay to close/open, close/open when it tries to connect to the house bank if it is low on charge.

It can stay wired as it was, and will work fine, but you still run the risk of cooking the diodes if you pass through the OFF position with the engine running.

 

[Maddog]

Running a new wire from the alternator directly to the house bank with a fuse at the battery end is the method I prefer. It allows for excellent voltage sensing, provided your wire is sized correctly, and also prevents you from every frying the diodes in the alternator as the alt will always see the house load. For working on the engine you simply pull the fuse to break the alt wire.

I have found that wiring directly to the start battery can cause the relay to close/open, close/open when it tries to connect to the house bank if it is low on charge.

It can stay wired as it was, and will work fine, but you still run the risk of cooking the diodes if you pass through the OFF position with the engine running.

What MS says. This is how I have mine, No problems for the last 2 years.

 

[Stu Jackson]

I agree, the alternator output should go to the house bank. Saves a LOT of potential future grief.

A parallel discussion held a while ago was on the C310 Forum, here, which explains why, too.

http://forums.catalina.sailboatowners.com/showthread.php?t=104505

 

[TDudley]

I got a email from Blue Sea and their vote goes for hooking th alternator throug the starter post.. I am going to that and complete the other side of the house and see what happens there.