Siemens Sinamics S120 Function Manual page 485

Trace evaluation:
● SS1 function is selected (time axis 0 ms; see bit "deselection SS1")
● Response bit "SS1 active" is set (time axis approx. 20 ms)
● The drive decelerates along the configured OFF3 ramp (p1135)
● Recording of r9714[0] (orange curve) shows whether the OFF3 ramp is active.
Not e
B ehavior for "SS1 with external stop"
When selecting "Safe Stop 1 with external stop (Page 90)" the drive is not braked along
the OFF3 ramp, but after the delay time (p9556) has expired, only STO/SBC is
automatically initiated.
● STO is activated (time axis approx. 720 ms; see bit "STO active"); at this point the speed
falls below the shutdown speed SS1 (p9560)
● A fault is generated if the envelope curve of the SBR function (Drive_1.r9714[1]) is
exceeded by the actual speed (Drive_1.r9714[0])
In contrast to SAM for Safety with encoder, this curve is not tracked according to actual
speed, but calculated using Safety parameters. Furthermore, this monitoring only
becomes active after a configurable time has elapsed (in this case the time is 250 ms).
This curve should approximately run in parallel to r9714 [0].
Not e
Time differences through internal c alculations
Small time differences (of the order of two to three Safety cycles (here up to 36 ms)) are
caused by internal calculations and do not present a problem.
Safety Integrated
Function Manual, (FHS), 07/2016, 6SL3097-4AR00-0BP6
A.3 Acceptance tests (recommendations)
Appendix
485