Technically there is no percific time for it as every stone has a different polishing time. Generally I find 2mins on each pad long enough. The good thing about the klindex pads is that they are a "prepare to polish" system so there isn't really any chance of over polishing (orange peel). The only way you will over polish is with the KP85 the time for this should be taken from the time of creating the "yoghurt" consistency so checking every minute will give you your time, this also comes down to what the client wants ie semi-gloss or high gloss (on occasions you may find finishing at stage 3 sufficient). On experience a lot of marbles will polish after 2mins or unless a dark marble like black, limestones and travs around 3-5 minutes.
Ill add this finally, we very rarely use the 1 & 2 steps the reason being these pads and any other pad were designed for Flat floors that are ones that have been ground flat! So we find the use of honing powder around a 320 grit (we would try 400/800 first) a brush combined with high alk or on a occasions a ph neutral cleaner more effective in the cleaning of the grout and the whole floor in one step then using the super shine no 3 then a polish. A lot more economical than using all 3 pads.
Hope this answers it....