Question about the time control setting of Shredder Classic 4

Question about the time control setting of Shredder Classic 4.

Why there are three different kinds of time controls as showed below in pic?

What do the 2nd and 3rd time control mean? do they have anything to do with the 1st time control or what? Just dunno why here in need of 3 different time controls,cuz I have tried that basically I just set one is yet enough,then what to do with the other two?

Waiting for answers from wisemen, thanks

Some longer over-the-board games can consist of two or three time controls, so Shredder gives that choice.

In a multiple time-control game, once you play the required number of moves for the first time control, you then proceed into the second time control. The same goes for the third time control, if one exists.

Sorry I don't get it,did you mean if one player makes enough moves as the 1st time control setting required,let's say,he has finished 50moves within 30min,then in addition to this，the 2nd time control will begin to take effect? baffled...

I　just wonder  how does it work,then I could know how to set the time control for the function of which I deem is quite important ,cuz I do like Shredder Classic with its user-friendly design.

I think you understand, but I'll go through an example,

Let's use the last standard choice in your pic, 40/120', 20/60', Rest 60'. Now, say that you complete your 40th move in 1 hr and 45 minutes, which reaches your first time control. Your clock would then start the second time control, but the unused 15 minutes from your first time control would be added to your alloted time in the second time control. So in effect, you would have 75 minutes to make 20 more moves.

Let's say you use 55 minutes to make your next 20 moves (from move 41 to move 60). When you make your 60th move, you've completed your second time control, and your clock would start your third (and final) time control. Also, your 20 unused minutes from the two previous time controls would be added to your third time control. So you would have 80 minutes to make all of the moves needed to finish out the game.

One more note. If you fail to meet any of your time controls in the required time, you would lose the game by time forfeit (i.e., flagging).