Commissioning
4.3 Creating a STEP 7 project
Connecting SIMOVERT MASTERDRIVES MC to the Technology-CPU
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Product Information, 03/2008, A5E00272072-05
SIMOVERT MASTERDRIVES Motion Control
Select the signal edge using the technology function MC_MeasuringInput in the user
program:
● rising edge
● falling edge
If you select another setting, the last valid value is taken over (rising or falling).
Response times for the measuring function
With the Technology CPU, the measuring function can be used in various configurations.
Depending on the connection of the axis (via PROFIBUS-DP) and the processing level
(position controller clock cycle or interpolator clock cycle) you must take into account
different response times for the measurement function in the application itself.
In the user program, measuring is controlled by calling the function block
MC_MeasuringInput. You can specify when the measuring function is to be active during the
call:
● immediately (without measuring window/active range)
StartPosition = EndPosition
● within a position-dependent measuring window
StartPosition < > EndPosition
For Measuring without measuring window with MC_MeasuringInput, the measuring input is
immediately activated.
The runtime up to the evaluation of the measured signal edge at the hardware input is
dependent on the configuration (refer to Table 1-1). To be certain to detect the measuring
edge, you must ensure that MC_MeasuringInput is executed earlier by this amount of
runtime in the user program.
When Measuring with measuring window, the task is only registered in the system with
MC_MeasuringInput. The measuring input is only activated when the axis is at the beginning
of the measuring window.
The runtime from reaching the start of the measuring window on the axis (mechanics) to
evaluating the measured signal edge at the hardware input is dependent on the configuration
(refer to Table 1-2). In order that the measuring input is active at the axis when the beginning
of the measuring window is reached, when calling the function, you must bring the start of
the measuring window forwards depending on the axis velocity and response time.
This also appropriately applies for the end of the measuring window. It is important that the
measuring input is no longer active when the end of the measuring window on the axis
(mechanical) is passed.
These runtimes can only be compensated using the configuration data
MeasuringRange.activationTime (or in the diagram "Probe configuration" in the input field
"Activation time of probe measuring range)
Note
The offset of the measuring window only functions reliably when the axis velocity
•
Within the measuring window is constant and is
•
Known before the function call.
