Device names

I'm wondering how NetWorker comes up with device names.  I just replaced a Dell 124T LTO-4 autoloader because the one we had went bad.  I muddled my way though deleting the bad one from within NetWorker and installing the new one.  My question is this.  The device name for the old autoloader was \\.\Tape2147483636, the device name for the new autoloader is \\.\Tape0.  What's up with that?  I've skimmed the 7.6 NetWorker Admin Guide but haven't found much yet.  I've also noticed that the device names for all of my VTLs are \\.\Tape2147483602, which is obviously similar to the device name of my old autoloader. 

I must have not done something correctly when I installed and configured the new autoloader, can anyone tell me what I screwed up?