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napalm204

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I have checked my deep cycle house batteries with a meter before starting the genset and they both measure better that 12.0.  But when I activate the battery disconnect switch and try to operate my 12-volt system, I do not have enough current.  When I run the genset everything works fine, of course, but the house batteries are not adequate for the electric step, lights, HWH or anything without the genset running.  I am sure I must have an interruption somewhere.  Where are the simple problem areas and where I should look first?

As always, I am grateful for any and all responses. 
 
You are confusing volts and amps. 12 volts is required but that says nothing about how well charged up the batteries are (how many amps it has available). Try charging up the batteries and see if that helps.
 
[quote author=napalm204]
  But when I activate the battery disconnect switch and try to operate my 12-volt system, I do not have enough current.  When I run the genset everything works fine, of course, but the house batteries are not adequate for the electric step, lights, HWH or anything without the genset running.  I am sure I must have an interruption somewhere.  Where are the simple problem areas and where I should look first?
[/quote]

Are you saying that you get NO power from the batteries for lighting, etc.., or just NOT ENOUGH power to run things like jacks, steps etc.?

If NO power at all, then I think you may have a blown fuse, or failing disconnect, between the converter and the batteries.

When the genset is on, does the converter charge the house batteries?  You should measure about 13.6vdc at the batteries when charging, not just 12v+.

If the batteries just don't seem to have enough power (but do provide some) then they are either defective or there is a bad (dirty or loose) connection somewhere in the house battery feed path.
 
When you "activate the battery disconnect", are you turning it off or on? And are you sure it is working?  That switch does just what it says - disconnects the battery from the wiring, so there would be no 12v power from the battery if that switch is in the disconnect position or has failed.
 
The "Disconnect" switch nomenclature and terminology can be quite confusing.  (e.g. when the disconnect is ON, the battery is OFF)

On my Bounder, I've had to adopt the mind set that when the switch labeled "Aux Battery Disconnect" is pressed on the top (which the mind usually equates with ON) it is actually turning the batteries ON.  When pressed at the bottom, it is turning the batteries OFF. 

The switch panel nomenclature, if taken literally, would suggest the opposite.
 
OP didn't mention the age/condition of house batteries.  12+ volts is only a relative number when considering the condition of a battery.  Load test the house batteries. 

Check all connections for corrosion and proper tightness of connections.

Sounds to me, based on info given, OP implied that some voltage is available.  Just not enough current to complete the job. 

It sounds like the genset is doing it's job.  Just Lou is on the right track, as well as Gary.



 
Lou is correct in that when I activate my battery disconnect, I mash the top of the toggle switch and this turns the batteries on.  The switch is actually labeled "use" and "store."  I have a glow-light inside that toggle that lights up when it is on.  I only 2-weeks ago made sure the connections were clean and tight and the electrolyte was at the correct level.

In addition, I have no power at all when I try to use the house batteries, so I will follow Lou's advice and look for a blown fuse.  I will also charge the batteries once again with the genset and see what kind of reading the voltmeter gives me.  I have tried to use the house batteries after running the genset for 2-hours and still have no house battery power, so there is a failure to launch somewhere.

Thanks to all.  I appreciate every comment and suggestion.  I will troubleshoot and see what follows.
 
If you are using a digital meter, your battery/s should measure 12.6v fully charged. Anything less than 12.6 wouyld indicate a state of discharge. At 12v you would be almost totally discharged. If the battery measures 12.6v after charging, look again at your connections, especially the ground cable where it connects to the frame.
 
gwcowgill said:
If you are using a digital meter, your battery/s should measure 12.6v fully charged. Anything less than 12.6 wouyld indicate a state of discharge. At 12v you would be almost totally discharged. If the battery measures 12.6v after charging, look again at your connections, especially the ground cable where it connects to the frame.
Click to expand...

  A side question.... Ain't technology great?  How did we ever run RV's when only analog voltmeters were available. Measuring between 12.0 and 12.6 volt would be virtually impossible without a lab-type meter. Now the digital meter is available for < 20 bucks. Hopefully they read fairly accurately. No bets.

Please don't thread-drift this post too much.

Carson FL
 
[quote author=carson]Now the digital meter is available for < 20 bucks. Hopefully they read fairly accurately.[/quote]

Don't tempt me Carson. Having worked for a company that supplied the first 2-chip set to a major DVM manufacturer, I have a story for the campfire about how I had to explain to designers the difference between precision and accuracy. Measuring a voltage to n decimal places with an accuracy of +/- (a lot) is no better than using a wet piece of string with one end placed on your tongue.
 
Tom said:
Don't tempt me Carson. Having worked for a company that supplied the first 2-chip set to a major DVM manufacturer, I have a story for the campfire about how I had to explain to designers the difference between precision and accuracy. Measuring a voltage to n decimal places with an accuracy of +/- (a lot) is no better than using a wet piece of string with one end placed on your tongue.
Click to expand...

I remember learning a similar lesson in grade school. If given a question of adding together two measurements say 2.5 inches and 4.8976 inches, the correct answer is not 7.3976 inches as a typical mathematician might assert. It's really 7.4 inches. It took me a while to wrap my head around the concept of significant digits as a youngster.
 
That's called rounding, nowt to do with what we're taking about.
 
carson said:
  A side question.... Ain't technology great?  How did we ever run RV's when only analog voltmeters were available. Measuring between 12.0 and 12.6 volt would be virtually impossible without a lab-type meter. Now the digital meter is available for < 20 bucks. Hopefully they read fairly accurately. .
With today's technology the old Simpson's are almost obsolete except when working with analog sensors. I'll keep both for now. I just wish we could do some seminars on reading and using the VOM someday. Maybe I will sit down and try to write a couple lessons if I don't lose my trend of thought which happens quite frequently now.

]
Click to expand...
 
One thing missing from the digital meter of today is good old parallax.  Why, with parallax, you could make a lot of things measure spot on - or not.
 
I only recall seeing a parallax adjustment on oscilloscopes  ???
 
[quote author=Molaker]Parallax adjustment on analog VOM's was head movement.[/quote]

Ah, yes, I recall that one Tom.
 
In my old Navy 'A' school (basic electronics), they 'bout beat us to death with parallax and how to avoid it.  It certainly was more difficult to delineat between 12.5 and 12.6 volts (actually, 28 vdc was the voltage d'jour in aviation).
 
Molaker said:
In my old Navy 'A' school (basic electronics), they 'bout beat us to death with parallax and how to avoid it.  It certainly was more difficult to delineat between 12.5 and 12.6 volts (actually, 28 vdc was the voltage d'jour in aviation).
Click to expand...

Fond memories of Norman, Ok and Millington, TN
 
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