Now we learn plc programming examples for siemens s7-300 plc,here some ladder diagram program.

FC1 variable

FC1 ladder diagram program

OB1 call Ladder diagram program
(1) Control requirements.
using a timer freedom to set the clock pulse generator function (pulse duty factor 1: 1)
(2) FC1 variable

(3) FC1 ladder diagram program

(4) OB1 calls ladder diagram program

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