I can't remember exactly, but as long as you don't exceed the limit by more than 40 km/h (less if within a town) then you don't have to worry. If you do, then you may lose your licence for 4 weeks iirc. I think you can collect up to 14 points or so before you lose your licence by default as it were. The points expire after two or three years.
DH usually gets 1 point and a 125 fine if that helps . I am a slowcoach careful driver <preens>.