Alternator charge for House Battery - intermittent

[rickschwolsky]

Preparing for a trip to Moab next week and all of a sudden I'm seeing that the house battery is intermittently charging from the engine when I'm driving. This is a new development - that I can see in real time on my Blue Sky solar controller and battery monitor.

The engine alternator is working perfectly - I can see that through a voltage meter -- charging the engine battery at 14.4 volts while driving. But all of a sudden the solar controller shows that the house battery isn't getting the same juice from the alternator.

Could this be as simple as a loose wire connection -- causing intermittent charging? My battery separator is brand new and has worked flawlessly --

Any troubleshooting advice would be welcome given our trip coming up. Thanks all --

Rick Schwolsky
Lafayette, CO

[vandiesel]

It may be that your battery is full and it is only topping it off.

[posplayr]

Seeing as no one else hand answered and you did not detail what parts you are using or how they are connected, I would assume that your "battery separator" is separating probably due to it determining the car battery is too high?

If you have a simple "constant duty relay" for a separator then it could be a loose connection but if it is happening while driving only then I would not suspect loose connections.

Of course go back over the connections. That is typically the first step in diagnosing electrical.

[rickschwolsky]

Thanks guys -- I will check the connections.
No matter what voltage my house battery shows when I start the engine -- it has always jumped up (13.5 - 13.8) when I run the engine. The past two days it has either shown the jump up, or hasn't budged from where it was in the morning (12.4 or so).

[N147JK]

Originally Posted by vandiesel

It may be that your battery is full and it is only topping it off.

Or, your house battery has failed internally and simply needs replacing. Do you have a spare you can swap in to test this, perhaps from another vehicle?

[rickschwolsky]

Thanks -- that would be depressing -- I just put in a brand new 200amp house battery last fall - and kept it pretty well charged through the winter -- Rick

[posplayr]

Originally Posted by rickschwolsky

Thanks guys -- I will check the connections.
No matter what voltage my house battery shows when I start the engine -- it has always jumped up (13.5 - 13.8) when I run the engine. The past two days it has either shown the jump up, or hasn't budged from where it was in the morning (12.4 or so).

Without knowing what you mean by a "battery separator" we can only guess (can you give us a clue?). However, when the 40 Amp-hr car battery and the 200 amp-hr haus battery are connected you will see some rise in voltage to the house battery depending upon SOC and RPM. If the Haus batt is low , it will take a while but eventually, it should get to 14.5V which is the setpoint of the alternator.

There is no evidence to suggest the Haus battery is shorted or bad. The logic that connects and disconnect seems to be shall we say "unreliable"

[rickschwolsky]

Thanks
By battery separator -- I mean the battery isolator that separates the house battery from the engine start battery -- which keeps the engine battery from drawing-down the house battery when camping. I've been trying to maintain the house battery all winter with regular charging -- but maybe it dropped low - I really appreciate your help.

[Scalf77]

What battery "separator/isolator/ACR" do you have? Also other than voltage your solar controller can not monitor current from the alternator.

-greg

[posplayr]

Originally Posted by rickschwolsky

Thanks
By battery separator -- I mean the battery isolator that separates the house battery from the engine start battery -- which keeps the engine battery from drawing down the house battery when camping. I've been trying to maintain the house battery all winter with regular charging -- but maybe it dropped low - I really appreciate your help.

Just as an FYI, although it may not seem important it is virtually not worth the effort to postulate various troubleshooting alternatives without knowing a specific set of components and when required a specific wiring configuration.

So while almost everybody knows what you, mean by a battery separator, nobody probably knows what type you have. And as I already stated without understanding the type we can not understand what logic there may be in the separator and so everyone is left guessing until you make the effort to specify the actual brand and part number.

Sorry, but this is the third time I have asked and you apparently do not understand the importance of this type of info to resolving your issues.