Chevrolet Repair: Altenator 1998 Cavalier 2.2L, altenator, alternator

Question
I just replaced a alternator on my girlfriends 1998 Cavalier 2.2L.  The alternator tested good on the bench but is only putting out 30amps once installed on the car.  I checked the grounds and followed the wiring as far as I could.  Any ideas on what to check next?

Answer
The alternator will only put out enough amps to run all the accesories and maintain the battery's state of charge.
if you do not have a tester that can put a load on the system, then you'll have to put all the accesories on and raise the rpm's to check output...unless you're using a digial tester.
I would verify that the alternator is actually only putting out 30a before going any further. Make sure you're puting the probe on the wire from the back of the alternator.