What is ON delay and OFF delay timer?

Answer 1

with an ON delay timer once the power has been appied to the timer unit, the timer contacts will change state-open/close after a preset time (for example A&B timers are adjustable anywhere from 0.05 seconds to 300 Hours)

with a OFF delay these contacts change state after the power to the unit has been removed then the preset time will time out (this count dosen't start until the power is removed