Are you referring to the machine where Raze will get in every time his hp drop low? If so there is a control panel alike this if I remember correctly, next to the so call generator machine. When you use it, it will like disable the machine for a short duration. But you had to do it before raze enter the machine to regenerate, else you wont able to stop him to regenerate. The best way is to kill Raze straight before he can even regenerate. If you are a warrior, you might able do so with thousand strike. I saw before some said stand in front of the machine and lure all the summon mobs on you, so they can block raze from accessing the machine. You can give it a try if you want.
