Statement List (STL) - DCE FEL ČVUT v Praze

Programming Examples
Statement List to control the Conveyor Belt
STL Explanation
O I 1.1 //Pressing either start switch turns the motor on.
O I 1.3
S Q 4.0
O I 1.2 //Pressing either stop switch or opening the normally closed contact at the
end of the belt turns the motor off.
O I 1.4
ON I 1.5
R Q 4.0
Example 2: Detecting the Direction of a Conveyor Belt
Q 4.0
The following figure shows a conveyor belt that is equipped with two photoelectric
barriers (PEB1 and PEB2) that are designed to detect the direction in which a
package is moving on the belt. Each photoelectric light barrier functions like a
normally open contact.
PEB2 PEB1
Q 4.1
Statement List (STL) for S7-300 and S7-400 Programming
B-4 A5E00706960-01