3.7.1. Overview of the STEP 7 programs

The table below shows the function of the individual program parts: During a measurement all program components are loaded.

STEP 7 program component Job in sending station Job in receiving station
Measuring program Communication program Sending of data in cycl. OB1 Receiving of data in cycl. OB1
Acquisition program
Control of measurement and recording of all measured values
  • Recording of measuring start signal
  • Measuring cycle time
 Control of measurement and recording of all measured values
  • Creating the ready signal
  • Measuring cycle time
Load program   Load of S7 controller (in OB1) Load of S7 controller (in OB1)

 

Composition of the cycle time

The figure below shows the structure of the STEP 7 programs and the definition of cycle times for modular and PC-based controller types:

 

"Minimum wait time" of WinAC:

The "minimum wait time" parameter of WinAC is a system parameter. This parameter is required to be able to run other applications or operating system functions on the PC in addition to WinAC.

To achieve a practical PC workload of approx. 50 %, the minimum wait time for all measurements with WinAC RTX is configured as follows:

 minimum wait time = Execution time!