A ladder logic program that can be used as a warning signal when equipment is moving, such as B. The conveyor motor is about to start.
When the START button SP0 is briefly pressed, the internal output INT_OTE is activated.
As a result, the contact B3/0 closes on SP0 to surround the output coil INT_OTE.
Additionally, contact B3/0 on the second rung closes to energize the timer coil, and contact B3/0 on the third rung closes to sound the horn.
After a delay of 10 seconds, the NC timer contact (4:0.DN) opens to automatically turn off the horn.
Press the REST button SP1 to reset the initial state.
test and run
Pressing the start button SP0, the input address is forced, causing the outputs of this rung to be true, they appear with the opposite sign.
On the second rung, since the condition is true, the timer is energized.
After 10 seconds timer is enabled opening the timer contact (T4: 0.DN) in the third rung.
This will de-energize the output coil and turn off the horn. The timer-accumulated value is reset to zero.
The internal output INT_OTE is closed and sealed via the control contact of push button SP0.