Siemens SINUMERIK 840D

11.03 3 Safety-Related Functions
3.1 Basic mechanisms of SI functions
© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
3-75
Example 2, delaying the transition from STOP F to STOP B
The same parameterization as in example 1 is shown in the following diagram.
However, when a STOP F occurs, no monitoring function is active. At instant in
time t2, a monitoring function is activated. ESR is only started if there is a
STOP F with active monitoring function.
Weiterfahren (ESR)
Bremsen an Rampe
= Stillsetzen (ESR)
t1 t2 t3
v
t4
Fig. 3-10 Speed characteristic of an SI axis when stopping with STOP F
The following actions take place at the individual instants in time:
t1: STOP F occurs, no response
t2: Any time after t1, a monitoring function is activated. At this instant in
time, the transition time to a STOP B is started and bits 1 in
$A_XFAULTSI and $VA_XFAULTSI of this axis are set.
t3: 500 ms after t2, braking starts along the parameterized ramp.
t4: STOP B is initiated 2.5 s after t2. The axis is already stationary
at this time. This means that pulses can be immediately cancelled.