zsoca, I'm sure that changing the belt will not trigger the trip switches, there must be something else. Did you by any chance push the machine manually over the limit while you have been working on it? Try to push the machine away from all end points and see if that helps.
You didn't take the power cables of when you changed the belt or did you?
Let me know when you find the problem, I'm interested what it is.
Sorry I don't know any technician in Hungry who could help you, you may have to call Bavelloni directly.