User manual

measured the idle current demand for more recent GM vehicles is about 5 times that

amount or about 60 milliamps. The idle time possible has been reduced to about a week.

GM seems to think this does not matter since most of these vans are in commercial

service and don’t sit idle.

Roadtrek addressed the problem of the vehicle battery going dead while parked by

replacing the isolator with a battery separator. The isolator allowed the vehicle alternator

to charge the RV battery whenever the vehicle was driven, but did not provide for

charging the vehicle battery when connected to shore power or running the generator.

The battery separator accomplishes this by connecting both batteries together whenever

the voltage on either the vehicle battery or the RV battery exceeds about 13 volts

indicating that charging is taking place.

Oddly enough all is not free, the battery separator typically draws about 10ma while idle

increasing the load. It’s not clear from the documentation which battery carries the load,

but I suspect it’s probably whichever one has the higher voltage. I’m of the opinion that

with the older vehicles the isolator is probably a better choice since it does not add to the

leakage problem.

Summary:

So, in summary there are 4 configurations covered by the simulator:

• Isolator equipped with converter directly connected to 12 volt loads

• Separator equipped with converter directly connected to 12 volt loads

• Isolator equipped with converters which bypass the battery disconnect.

• Separator equipped with converters which bypass the battery disconnect.

This is a "work-in-progress" and there are very likely a few bugs and it may not work

correctly.

Finally, it is a basic "functional" simulator and does not model real detail. Beyond the

states of the various switches and a dead, poor and fully charged battery, it does not

understand other conditions.

Troubleshooting Tips and Common Questions

Here are a number of situations and possible solutions. Remember a set of symptoms is

just that a set of symptoms and the actual cause may not be the same as the one

described.

The generator dies as soon as I release the starter switch.

The generator has an oil level interlock which will inhibit the ignition when the oil is low.

So check the oil level first. While you hold the starter switch down, the generator fuel

pump and ignition lockout are powered from the battery. When the switch is released, the

controls are running off the generator output. There are several things which can create

this problem including the control board, regulator board and dirty slip rings. The Onan