 The AirForce 1 Turbines (and most other battery charging turbines) need to be kept under load at all times  The reason for this is that without the load, it could overspeed and damage itself both electrically and mechanically  As the battery voltage climbs, the load on the turbine reduces which causes an increase in speed. Obviously when the battery is fully charged, you do not want to continue charging the battery so we have to find an alternative load for the turbine  The way this is done is by switching in a “dump load” gradually as the battery becomes fully charged  This is done by the Charge Controller, who’s job is purely to monitor and control the charging of the batteries  It is a popular misconception that it sits between the turbine and the batteries – this is incorrect (with Wind Turbines!)  Think of the Charge Controller as a dimmer switch which adjusts the power going into the dump load, which keeps the battery voltage at its recommended levels during charging, by siphoning off the excessive power  This excess power is usually converted to heat in either air or water

 The Xantrex & Tristar Charge Controllers have 3 modes  Diversion as used with Turbines  Solar Control, which regulates the charge from Solar PV Panels  Load Control, which turns off a load if the battery voltage drops below a certain set value

In Diversion Mode