Safe Software Cams (4 Cam Pairs) - Siemens SINUMERIK 840D sl Function Manual

Safety Functions Integrated in the System/Drive
6.8 Safety software cams and safety cam track (SN)
Effects when SN responds
Warning
!
When defining cam positions, please note that the function only monitors the
actual position thus making (predictive) sensing of cam signals impossible.
The cams are only considered as being safe if they were safely referenced. This is
the reason that the user must link this SGA in the SPL with the corresponding
SGA of the cam functionality.
Response times
S Response times without cam synchronization
typical1 interpolation clock cycle + 1.5 monitoring clock cycles
maximum 1 position controller clock cycle + 4 monitoring clock cycles + 2 inter-
polation clock cycles + 3 PLC cycles
S Response times with cam synchronization
typical1 interpolation clock cycle + 2.5 monitoring clock cycles
maximum 1 position controller clock cycle + 5 monitoring clock cycles + 2 inter-
polation clock cycles + 3 PLC cycles
6.8.1

Safe software cams (4 cam pairs)

Note
If more than 4 cam pairs are required, then the "safe cam track" function must be
used (refer to Chapter 6.8.2, "Safe cam track").
Description
There are 4 pairs of cams (SN1, SN2, SN3, SN4) available for each axis. Each
cam pair consists of a plus cam (SN1+, SN2+, SN3+, SN4+) and a minus cam
(SN1–, SN2–, SN3–, SN4–). Each cam signal can be individually enabled and con-
figured via machine data. The cam signals are output via SGAs.
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SINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) – 05.2008 Edition
© Siemens AG 2008 All Rights Reserved
05.08