User manual

condition function. When you push and hold the test button, the display will show the

battery condition as well as the levels for the LP gas, fresh water and holding tanks. The

battery condition lights display the current battery voltage. This may or may not be

representative of the battery condition. The “C” light will be on if the voltage is above

about 12.7 volts, the “G” light comes on at about 12 volts, the “F” light comes on at about

11.3 volts. The “L” light will come on with less than 5 volts. This means the battery has

some charge, but does not tell you much more.

With an accurate volt-meter and allowing the battery to sit without charging or discharging

for a time, you can assess the state of charge of a battery. This display does not give that

level of detail. With a good fully charged battery and not much load, the “C” will often

display even when charging is not taking place. This is particularly true if you have been

charging the battery and have recently stopped. The “surface charge” will take some time

to dissipate if there is very little load on the battery. I did not attempt to show this

behavior on the simulator so it won’t show “C” unless charging is taking place.

Note that while charging, the display should always show “C” regardless of the condition

of the battery. Let me repeat, when charging, it tells you nothing about the state of

charge of the battery.

Just like the actual panel, you have to hold down the button for the display to work.

Depending on the configuration, it may or may not work with shore power connected and

the battery disconnect in the off state. Vehicles with the direct connection will display the

converter voltage instead of the battery voltage when connected to AC power with the

battery disconnect turned off.

Alternator

The alternator, driven by the vehicle engine, produces power

to charge, not only the normal vehicle battery, but also the RV

battery. A moderate drive should be enough to charge the all

of the batteries under normal conditions.

Note that with “isolator equipped” vehicles, the alternator

connections are NOT the same as a standard vehicle. The

Roadtrek factory modified the production vehicle wiring to

accommodate the isolator. These changes often confuse

auto mechanics who work on automotive electrical systems. More than one battery and

or alternator have been replaced, when in fact the problem was the isolator. The "output"

terminal of the alternator will have voltage present and produce current when the engine

is running. With the engine and ignition off, the "output" terminal should have no voltage

present. The voltage present at the alternator terminal will be noticeably greater than the

vehicle battery voltage. This is normal, but again may alarm the technician not familiar

with “isolator equipped” vehicles.

Use caution, because modern digital voltmeters do not “load” the circuit and it’s easy to

misinterpret readings. You may for example read an apparently low voltage on the

alternator stud which is due to the tiny diode leakage current. This is perfectly normal

behavior.