3 Safety-Related Functions
11.03
3.6 Safe software limit switches (SE)
© Siemens AG 2003 All Rights Reserved
3-112
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
3.6.1
Effects when an SE responds
!
Warning
The SE function does not predictively monitor the SW limit switches, i.e. the
axis stops after passing the limit position. The distance traveled after the SE
is dependent on
how the function is parameterized (monitoring clock cycle, stop response...),
the current traversing speed and
the design of the axis.
When an axis passes a "safe software limit switch", a stop response configured
in the following machine data is generated:
For 840D
MD 36962:
$MA_SAFE_POS_STOP_MODE
For 611 digital
MD 1362:
$MD_SAFE_POS_STOP_MODE
The user can select either STOP C, D or STOP E.
•
The configured stop response is initiated.
•
The relevant alarm is displayed.
•
Traverse the axis to a position in which the monitoring does not respond
(refer to Description of Alarm "safe software limit switch passed" in
Chapter 6, "Alarms"). The "user agreement" must be canceled (SE is then
de-activated)
or
change over to the other "safe software limit switches".
•
Acknowledge the error message according to the configured stop response
(refer to Chapter 2, "Safe response via shutdown paths and STOPs")
If the "safe software limit switch" function is active, the system timing is as
follows when the limit position is passed:
Configurable stop
responses
Effect
Acknowledging and
moving away
Timing when "safe
software limit switch"
is actuated