1991 Grand am not charging a good battery

[apurso]

I have a 2.5 liter LE 2 door coupe. I thought it was the alternator because when i did get it started the DC volt meter was dropping voltage and not gaining. I bought a new alternator and it is still doing the same thing. Is there a voltage regulator that may be causing the is because the battery was working fine just a week ago?

 

[melsg5]

the regulator is in the alternator. Check the plastic plug with the 2 wires that goes to the alternator for a broken wire internally using a voltmeter.