Basic PLC Ladder Programming Examples 5

Basic PLC
Ladder Programming Training Examples for Beginners.

friends here we are starting here a series of Free Training on PLC
Ladder Programming training & tutorials.These PLC Ladder Programs
are important to get basics of Ladder programs.

Ladder Practice Problem: 

The production line may be powered off accidentally or turned off for
noon break. The program is to control the counter to retain the counted number
and resume counting after the power is turned ON again. When the daily
production reaches 500, the target completed indicator will be ON to remind the
operator for keeping a record. Press the Clear button to clear the history
records. The counter will start counting from 0 again.
PLC Ladder Programming Practice Problem 5
 Topics Covered in this example is Latched 16 bit UP counter.

of PLC Inputs Required
                 X0 – Product Detecting Sensor.
                 X1 – Production Counter RESET/Clear

                      Number of PLC Outputs Required

                Y0 – Production Counter Target Completed.

                     Number of PLC Counter Required

                 C120 – 16 Bit Latched Counter. (Max Count =32,768)

PLC Ladder Programming:

PLC Ladder Programming Practice Problem 5

PLC Ladder Programming Description:

The latching counter is demanded for the situation of retaining data
when power-off. 

When a product is completed, C120 will count for one time. When the
number reaches 500,
target completed indicator Y0 will be ON. 

 For different series of PLC, the
setup range of 16-bit latching counter is different.


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