Electrical Failure on Take Off

[Pete Somers]

Hi all
OK, if the RED HI light is on and you had an overvoltage, you would notice as some electrical equipment would fail, and a high indication on the ampmeter would be a clue.

However if the RED HI light is on all the time even when the engines are shut down, the HI/LO sensor is inop.

This unit is mounted on the port side of the center console, top above the HYD Power pack.

The big diodes-
They are wired into both alternator output and a reed relay is connected across the diode.
In normal operation the diode is forward conducting and the relay sees about a 1 volt drop across the diode and remains de-energized.
Should an alternator fail the votage drop across will be approximately equal to the buss voltage and the relay will energize and put a ALT OUT light on.

The HI/LO sensor is field repairable however, they do not cost all that much.

Hope this helps

Pete