Timing Relays

A timing relay has two major functions: On-delay and Off-delay timing. An arrow is used to denote the function of the timer. An arrow pointing up indicates an On-delay timing action. An arrow pointing down indicates an Off-delay timing action.
On-delay and Off-delay timers can turn their connected loads on or off, depending on how the timer’s output is wired into the circuit. On-delay indicates that once a timer has received a signal to turn on, a predetermined time must pass before the timer’s contacts change state. Off-delay indicates that once a timer has received a signal to turn off, a predetermined time must pass before the timer’s contacts change state.