Siemens SINAMICS S120, Function Manual

Page: 188 / 1094

Servo control
4.20 Central probe evaluation
Drive functions
188
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
Measurement buffer
Each measuring pulse input of a Control Unit 320-2 or 310-2 has one memory for maximum
16 measured value entries (8 rising and 8 falling edges).
The measured values for rising and falling signal edges are sequentially written to the
memory. If the memory is full and a new measured value is entered, all entries move down
by one location and the oldest value drops out. This means that in the case of an overflow
the latest 16 values are contained in the memory. When reading out an entry, the oldest
value is taken from the memory. The remaining entries move down and make space for a
new entry (FIFO principle).
Remarks
Other applications can also read the probe status and evaluate the probe measured values.
Example:
EPOS controls its probes axis-specifically. A control system can connect to the probe to read
its data and integrate the information into the drive telegram.
4.20.1 Examples
Examples of probe evaluation
Hex values in MT_ZSB from the above example:
● 0 hex = time stamp from probe 1, falling edge
● 8 hex = time stamp from probe 1 rising edge
● 1 hex = time stamp from probe 2, falling edge
● 9 hex = time stamp from probe 2, rising edge