Battery gauges

aero3113

I just had these questions pop in my head. The port and starboard battery gauges on the dash only read the starting batteries? The gauge on the breaker panel in the cabin reads only the house batteries? 

reneechris14

I have one the 12volt (cigarette lighter) plug in the dash I believe that is from the house bank. 

Ian

@aero3113 thats how I figured it.

Spyderweb

Same here.  Plus I figured the breaker panel gauge reads about .2 volt lower than a reading taken directly off the house batteries

YYZRC

Delete!

aero3113

@YYZRC , I believe the “generator starter battery” is also the starboard engine starting battery.

aero3113

@YYZRC , you only have 3 batteries installed? My 330 has 4. 2 starting and 2 house.

YYZRC

Maybe I'm confused then!  I have one battery on the starboard side (group 27) and the other 3 are on the port side (1 group 27 and 2 group 31).

aero3113

Yes, should be 3 port (1 starting and 2 house) and 1 starboard (starting).

benvenuttioki

I've been chasing electrical gremlins and found this thread. I've thought but never confirmed that starboard start battery is also generator battery. To test this I turned the rotary gen battery switch off and to my surprise the starboard engine rocker switch on that panel stayed green and engine still started. Can some explain this behavior or point me to the actual gen battery? I thought the rotary switches disconnected labelled batteries from all loads. Could this just disconnect stbd start from gen?

YYZRC

My 350 uses the port battery for the generator (even though the generator is on the starboard side).

If you look at your port starting battery, there should be a label on one of the positive cables marked “Generator”. Mine has two positive cables - generator and engine.

I would be surprised if yours was different. 

benvenuttioki

I wish it were that easy! Two positive leads on both start batteries and no labels anywhere. 
I guess it really doesn't matter, as long as gen start isn't on the house. That's where my problem lies. House batteries aren't charging while underway, or if they are the charge is way less than what the fridge and electronics suck down.  Electronics have intermittent problems after even short runs. Will replace batteries next season, but need to figure out why they aren't charging.

raybo3

You might be chasing ghost. Have the batteries load tested, they might be on the way out.

LaRea

If the generator isn't right next to the battery, there should be a disconnect switch.  I think the recommended max distance is 3 feet from the battery.  

As I told somebody else here recently - either trace each cable from source to load(s), or disconnect each battery one at a time, and see what stops working. Best way to be ready for problems when they happen. 

YYZRC

@benvenuttioki your isolator could be the culprit. 

benvenuttioki

@raybo3, I suspected the house batteries were about shot before the season. I had the yard test them before we were in the water. I suspect they didn't really load test. Will be more specific.

@LaRea, saw you post on disconnecting batteries. No time this weekend. I lost patience trying to trace. By disconnect, do you mean something other than the rotary in the cockpit?

@YYZRC, thanks. Will make that part of checks. 

I want to make sure that any problem other than bad house batteries is found and fixed this season. 

Question for group: Do the house batteries charge from the engines while underway? I thought they did, but owners around me say otherwise.

Grahamu

Providing your isolator is working and wired correctly your alternators will charge "all" batteries.

YYZRC

benvenuttioki said:

I wish it were that easy! Two positive leads on both start batteries and no labels anywhere. 

On mine, the labels were just under the corrugated cable covers near the terminal. 

LaRea

@benvenuttioki - for a battery terminal that has two wires connected, remove one wire and leave the other wire connected.  Then try to start the genny and engines, and see which one stopped working. 

YYZRC

@larea what would the fourth wire be for? Something to do with DTS/Joystick?

LaRea

I'm not sure how newer models are wired, but each starter battery powers the starter plus three other circuits:

DTS controller at the helm 
DTS actuator
Trim pump 

Those circuits all use much smaller wires.  If there aren't any small wires connected to the batteries, maybe there's a subpanel with breakers for those circuits, with a single large wire from the battery to the subpanel.

benvenuttioki

From each starter battery I've got one small and one large connection. I didn't look under the corrugated covers. Will give that a look and try disconnecting things next weekend. I should know what goes where for power. Shame on me for not doing this sooner!

I'll ask yard to take a look at isolator. Thanks for continued support, folks!