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Controlling the press - STEP7 / LAD

Two actuators act together as a hydraulic press. The press starts after holding two start buttons for 2 seconds. (There is only one "finger" cursor arrow on the screen, so that one button is a switch)

The press is working for 5 seconds and then it goes back to the initial position.

The controll program built in LAD consists of only one main block - OB1

The first network carries out the following task: after pressing two start buttons it triggers the timer T1 and waits for 2 seconds.

Timer T1 sets the decimal output Q0.0

that starts the press for 5 seconds (counted by timer T2).

It also sets the decimal output Q0.7 and turns the Horns on.

The decimal output Q0.5 and Q0.6 are used for indicating status: Working, Ready.

Display screen 16*5 LED light - STEP7 / LAD

The controll program built in LAD consists of only one main block - OB1

Program is in block OB1

There are two timers T1, T2 on the first network. Both timers switch on and off one another and set the memory bit M0.0

Changing state of the M0.0 causes the counter C1 to count up - it increases the value stored in MW2.

Exceding the limit resets MW2 - so the counter C1 counts over and over again.

The following blocks shifting left or right the picture stored in the array arr and send the result to the OUTPUTS from QW0, QW8

OUTPUTS are assigned to the appropriate LED lights on the screen.

Programming the calculator - STEP7 / LAD

The PLC program working out the mathematical operations consists of one block OB1 and function FC2

Networks: 1 and 3 invoke the function FC2 which performs the entering number task.

Networks: 2 and 4 store the entered number into the proper memory field MW2 or MW4.

Networks 5 and 6 send the first or second number to decimal output QW0 that is assigned to 8-bit indicator on the screen.

The decimal inputs I1.4. I1.5, I1.6, I1.7 and I2.1 correspond to "/", "*', "-", "+', "CE" calculator's key on the screen after pressing any of them the first entering number is switched to the second entering number.

Network 8 set res_no - show result variable after pressing I2.0 "=" key

Networks 9, 10, 11, 12 do one of the four math calcultions.

Next the PLC program shows the result (Net13), clears the memory fields after pressing the CE key (Net14), switch to the second number, select proper math operation.

The auxilary function FC2 is invoked after pressing any digit from "0" to "9"

Network2 shifts the entering number left (multiplies by 10)

then a new number is added to the entering number

Two actuators and one gripper machine

Control valve keeping the flow

Other program SimpleScada.

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