Safety Functions Integrated in the System/Drive6.5 Safely reduced speed (SG)05.086-151© Siemens AG 2008 All Rights ReservedSINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) – 05.2008 EditionTable 6-12 Selecting speed limit values for SGsSGESG selectionBit 1SG selectionBit 0Description= 0 = 0 Speed limit value for SG1 active= 0 = 1 Speed limit value active for SG2 1)= 1 = 0 Speed limit value for SG3 active= 1 = 1 Speed limit value active for SG4 1)Note:1) The SG limit values SG2 and SG4 can be finely graduated using the SG override (seeChapter 6.5.4, ”Override for safely reduced speed”.The active SG stage is displayed using SGA ”SGA active bit 0” and ”SGA active bit 1”.Changing–over the speed limit valuesA changeover from a lower to a higher speed limit value takes effect instanta-neously without any delay.When changing–over from a higher to a lower limit value, then a delay time isstarted that is parameterized using the machine data(refer to Figure 6-12, ”Timing when changing–over from a higher to a lower speedlimit”).for 840D sl:MD 36951: $MA_SAFE_VELO_SWITCH_DELAYfor SINAMICS S120:p9551: SI motion SLS (SG) changeover delay time (Control Unit) /The axis/spindle must be braked sufficiently during the delay time so that it hasreached the reduced speed that is below the new limit value when the delay timeexpires. However, if the actual speed is higher than the new limit value when thetime has expired, an appropriate alarm is output with the configurable stop re-sponse.
