When the RUN_SWITCH is turned on it will turn on both the timers T4:2 and T4:3 .and the output STR_MOTOR will be turned on . As the NC contact of timer 4:2 has been used the output HEAT_COIL will remain high for 10 seconds as after 10 seconds the timer will be on which activates T4:2 DN and turns it into NO.in between the output DISCHARGE_PUMP is on till the output T4:3 DN goes low . As T4:3 is delay off counter ( total time = base time * preset time in seconds)it will be turned on initially means turn T4:3 DN into nc and after 5 seconds it will be off making the contact no again . After the RUN_SWITCH is off all the outputs remains off as the timers are loaded with the preset values . on again pressing RUN_SWITCH it will again process again .
6. Consid shown in the discharge pump to show when they are on and off. er the ladder program sho...