Why would you not know what has went wrong?  I guess I’m missing something here.  I guess we should evaluate the failure modes of the alternator.  If it is overloaded or shorted, the ANL pops and its disconnected.  This occurs at about 80A on an ANL limiter correct?  If the internals of the alternator fails, the circuit breaker pops the field and again, its dead.  If an over/under/runaway voltage condition occurs, the regulator gets it and shuts it down.  If the regulator has failed, the alternator is dead anyway because of not field.  If the belt to the alternator breaks, no output.

Shannon,

 

There is another way.  I had a circumstance where a failing voltage regulator started to overcharge the battery.  The regulator allowed the bus voltage to get to about 15.1 volts (12 volt system, 14.3 is the usual running level) before the VM EPI 800 System flipped on one of my idiot lights (VOLTAGE).  After pulling the field breaker, I switched on the Essential Bus and turned off the Master.  Returning to the airport I had departed just 15 minutes before was no problem.  In the pattern I was able to turn the master back on to power the gear down and engage the flaps plus I still had about 8 gallons still in my 9 gallon header.  I would not have liked the situation to be more remote and at night and in IMC.  BTW, B&C claimed it was everything but the regulator - miswired sense, resistance on the field, etc.  I replaced the regulator and all was well.