Originally Posted by Sandiegodoug
So what good is the lights that come with the solera. I thought they were indicating the voltage of the system
And a digital dc voltmeter was a more accurate indicater of the charge state
First thing to understand is that coaches are set up to be plugged in at parks when they leave the factory. Most don't even come with true deep cycle batteries. The lights show you that the coach is plugged in and the converter is working. The digital readout shows the active voltage at the moment in the SYSTEM. When you unplug...it shows the ACTIVE voltage on the battery powered system at the moment...with the current loads and with any surface charge remaining on the battery plates after charging.
The lights and the meter can tell you:
Things are working.
Things are not working.
And things are dead.
Which is all you need if you plug in 99% of the time.
It cannot tell you the state of charge of the battery which requires a 24 hour wait in a static (i.e. not connected) state after charging to insure the SURFACE CHARGE is dissipated at you get a true reading.
You can eliminate the WAIT period with a load tester which can remove the surface charge. They look like this:
If you boondock
you will need at LEAST a couple of hundred amp hours of true deep cycle batteries in your bank and I strongly recommend a true battery monitor that will tell you in real time the state of charge of your battery, how many amps you are pulling from them NOW, and all together so far, WHEN it is time to recharge (at 50% down ,,, not when the lights go dim) and other interesting stuff like exactly how many amps that fridge lighter uses and how much stuff still uses when you turn the battery switch to off...(parasitic loads). In addition to making your camping less worrisome... it will pay for itself by not having you replace batteries that have been murdered so often. About $150 bucks.
Disregard the above paragraph if you don't boondock.
Hope that answers your question.
Oh yeah... the maximum voltage reading for a 12V battery is 12.7 Volts if NEW and 100% charged. Anything higher and you are reading the charger/converter voltage OR the surface charge left on the battery after charging.