Timers are used to measure and control time in automation systems. There are different types of timers including on delay timers, off delay timers, and on/off delay timers. Exercises are provided to design control circuits using timers to run multiple motors sequentially or simultaneously based on start and stop signals with different motors stopping after set time delays.

2. Automation Lec3
BY: Mahmoud Hussein

3. Timers
 Timer : is a component used to measure a time after time ,change contact depend
on your function

4. Timers
 Timer types:
 On delay timer
 Off delay timer
 Off delay with auxiliary supply timer
 On/off delay timer
 Difference between on-delay and off delay

5. Exercises
 Design a control circuit to run two motors with start button and by pressing stop
button motor one stop and after time M2 stop

6. Exercises
 Design a control circuit to run two motors with start button and M1 stop after a
time and M2 stop after stopping M1 with a time

7. Exercises
 Design a control circuit to run M1 with pressing start button and after T2 M2 run
and after T1 M1 stop after T3 M2 stop

8. Exercises
 Design a control circuit to run motor with start button after a time motor will stop.
 Design a control circuit to run motor1 by pressing start button and stop button
running M2 for a time
 Design a control circuit to run 3 motors that by pressing start run motor 1,2 and
after T1 motor two stop and pressing stop button motor1 stop and M3 run run for
a time.

9. Complete projects