In an application where different time values are needed for the on and the off delay (lets say the timer is ON for 2 minutes and then the OFF time needs to be 10 minutes for another process to occur) there are some time delay relays that have separate adjustments to allow for individual adjustment of these times.
These can sometimes be referred to as repeat cycle timers or Recycle timers. For some examples;
The Omron H3CR-F series features a hand dial to set each of the on-off times individually and small knobs in the face of the units you can turn with a screwdriver to adjust the units of time for each individually.
The TE Connectivity Potter and Brumfield CR series features Individual ON and OFF time adjustment knobs
There are some other series as well that have the individual adjustment features so here is the full list of parts we stock currently