Siemens Sinamics S120 Function Manual page 132

Servo control
3.19 Central probe evaluation
2. Signal source, synchronization signal in p0681.
3. Signal source, control word probe p0682.
4. Transfer with the communication interface PROFIdrive.
5. Synchronizing and monitoring isochronous PROFIdrive
6. Prerequisite for measurements is the synchronization between the control and drive.
7. Setpoint transfer at start time To and actual value transfer at instant in time Ti in the
8. Time stamp: Format (drive increments, NC decrements)
9. Each valid time stamp in the drive is incremented by 1 in order to make a differentiation
10. The value "0" in the interface is an invalid time format and indicates that a measured
11. Sequencer for the control/status word processing
12. Monitoring functions (sign of life)
13. Faults
Note
Time-critical data transfer
The status information E_DIGITAL and A_DIGITAL in telegrams 39x are not subject to
any precise time restraints according to the specifications. The transfer of E_DIGITAL and
the output of A_DIGITAL is realized independently of the PROFIBUS cycle clock with the
PROFIdrive PZD sampling rate according to p2048. Depending on the module, this can
be set to between 1 ms and 16 ms. As a consequence, deadtimes must be expected for
the transfer of output values and the feedback signal of input values.
Although the probe status word MT ZSW is identical with the content of E_DIGITAL, it is
however directly transferred in PZDs. As a consequence, for time-critical applications
measuring probes or cams should be used.
Central measuring with handshake
With p0684 = 0, you activate the evaluation technique with handshake for the central probe
evaluation. You can evaluate a maximum of one positive and/or negative edge per probe
within four DP cycles.
T
DP
T
MAPC
new setpoints).
1. Transfer, control word probe (BICO p0682 to PZD3) at the start instant To in the MAPC
2. The measurement is activated with a 0/1 transition of the control bit for a falling or rising
130
PROFIBUS clock cycle (max. 8 ms).
between a valid measuring time zero and an invalid time format. This increment is
removed again by the higher-level control.
value is not available.
= PROFIBUS cycle (also DP cycle)
= master application cycle time (time grid, in which the master application generates
cycle.
edge in the probe control word.
Function Manual, (FH1), 01/2012, 6SL3097-4AB00-0BP2
Drive functions