Alternator plug voltage

[Ben perry]

Hi all had a alternator die So fitted a good one I had spare and was humming not charging and the alternator body was warm quickly just wondering what the voltage should be on small plug wire it’s probs a dead alternator but as it’s in my kangoo just want to do as many checks as poss so I kno that I haven’t caused this I just need to make sure it’s not killing alternator befor I go new

cheers again