Siemens SINUMERIK 840D sl Function Manual page 290

Data Description
8.1 Machine data for SINUMERIK 840D sl
36950
MD number
Default value: 0.5
Change becomes effective after: POWER ON
Data type: DOUBLE
Significance:
Special cases, errors,...
Additional references
36951
MD number
Default value: 0.1
Change becomes effective after: POWER ON
Data type: DOUBLE
Significance:
Special cases, errors,...
corresponds with ...
8-290
SINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) – 05.2008 Edition
$MA_SAFE_MODE_SWITCH_TIME
Tolerance time for SGE changeover
Min. input limit: 0
Protection level: 7/2
SGE changeover operations do not take effect simultaneously owing to variations in run
times (propagation times) for SGE data transmission in the two monitoring channels. A
crosswise data comparison would, in this case, output an error message.
This data is used to specify the period of time after SGE changeover operations during
which no crosswise comparison of actual values and monitoring results is carried out (ma-
chine data is still compared!). The selected monitoring functions continue to operate unhin-
dered in both monitoring channels.
A safety–related function is immediately activated in a monitoring channel if selection or
changeover is detected in this channel.
The different run time (propagation time) is mainly caused by the PLC cycle time.
System–related minimum tolerance time 2 x PLC cycle time (maximum cycle) + 1 x IPO
cycle time.
The variations in the run times in the external circuitry (e.g. relay operating times) must also
be taken into account.
/FBSI/ see Chapter 7.1: "safety–related input/output signals (SGE/SGA)"
$MA_SAFE_VELO_SWITCH_DELA Y
Delay time, speed changeover
Min. input limit: 0
Protection level: 7/2
A timer with this value is started when changing from a higher to a lower safely reduced
speed – or when a safe operating stop is selected when the safely reduced speed function
is active.
The parameterized value must be selected as low as possible.
While the timer is running, the speed continues to be monitored against the last selected
speed limit value. During this period, the axis/spindle can be braked, for example, from the
PLC user program, without the monitoring function signaling an error and initiating a stop
response.
1. The timer is immediately interrupted as soon as a higher or identical SG limit (i.e. to
that which was previously active) is selected.
2. The timer is immediately interrupted if "non–safe operation" (SGE "deselect SBH/
SG=1) is selected.
3. The timer is re–triggered (restarted) if, while the timer is running, a changeover is made
to a lower SG limit than was previously active or to SBH.
Max. input limit: 10.
Unit: s
Max. input limit: 600.
Unit: s
© Siemens AG 2008 All Rights Reserved
05.08