What does the battery isolator do?

[jipjob]

Sent: 3/1/2004

This is a Simple question by a simple guy  What does the battery isolator do? and how do I check it to see if it ok? Thanks Jon

[UluzYarx]

Sent: 3/1/2004

Your battery isolator switch switches your battery off or on.

Saves you taking the main wire off your battery.

If you switch the isolator switch off when you lay your Winnie up for a few days, that battery doesn't go flat.

Dave

[Oz]

Sent: 3/1/2004

Exactly what Dave said,

     When you start your engine, you are of course using your engine battery.  When you run your coach lights and accessories and not plugged into 110v shore power, you are drawing off your coach battery(ies).

     In order to avoid draining your engine battery when running your lights and accessories off 12v,  an isolator is installed and is controlled by a battery switch on your dash (often called the MOM switch).  The old model Winnies simply had an On/Off switch.  The newer old ones have  an On/Off/Mom (momentary) switch.  This provides additional power from your coach batteries to help in starting the engine if needed (for a full explanation on the use of this switch, use the message search for MOM or battery switch).

       You can now get regulators that are installed in your battery/isolator configuration that will automatically read the voltage present in both your coach and engine batteries as well as isolators that have a regulator built in.  While driving, the regulator will always recharge the engine battery first if the voltage is low and then the coach batteries.  If while charging the coach batteries, the engine battery voltage drops, it will switch back to charging that battery until fully charged and then, back to the coach batteries.  Regulators can be installed with any isolator system and are not very expensive, around $40.

New style isolators can be VERY expensive and there are about a gazillion available but, you can get OEM style isolators for around $40 and they work very well. - Sob

[mightybooboo]

Sent: 3/1/2004

If its the solenoid looking thing make SURE its a continuous duty one,NOT an intermittent like a starter relay solenoid.
BooBoo