Connecting alt from 2nd engine to house bank. Where should sense wire go?

[hulakai]

Hi all, hope this is a quick/easy one that someone can help me with....

I have two engines, two batteries/banks, and two selector switches (one sends power to the engines and one to the house). Engines both start from the same source but I can't have both alternators charging the same battery. I want to connect one of the alternators to the house battery.....but where exactly should I connect the sense wire from the second alternator? If I leave if as is then the 2nd alternator will be sensing voltage on a different battery than it is charging. I'm considering connecting the output of the 2nd alternator to the house bank feed at the selector switch (shorter cable run and it's zero gauge wire from there back to the bank). It seems to me that if I connect the sense wire in the same spot, it's likely to sense the voltage output from the alternator instead of the voltage in the bank.

Am I missing something?


Thanks

Kevin

 

[alldodge]

Re: Connecting alt from 2nd engine to house bank. Where should sense wire go?

Hulakai - I seem to have given you some bad advise on my first drawing. After thinging about it and seeing your new post I have seen my error. You first mentione that your wiring was fried so I didn't know what I was dealing with and still don't fully. The previous owner could have put something together way out and therefore this is my uncertainty. Either way the charging circuits either have to be totall seperated or they have to use an Isolator. This image has the systems seperated



In the above system you will need dual purpose (deep cycle/starting) batteries for the house. These allow the house to pull the batteries down further without damaging them as they would with regular starting types.

The only other way to have one alternator charge both banks is with an isolator. One ALT will need to be disabled or removed. To disable just remove all the wires. The isolator will need to be placed between the ALT output to the Isolator, then from the isolator to both battery banks.

Sorry for over thinking this the first time.

 

[Don S]

Re: Connecting alt from 2nd engine to house bank. Where should sense wire go?

Why not use an ACR and use both alternators to charge both battery banks ?

Go here Battery Management Wiring Schematics for Typical Applications - Blue Sea Systems and under the Select a System box, select 2 engine, 2 batteries.