Siemens SINUMERIK 840D Description Of Functions page 200

3 Safety-Related Functions
3.13 Behavior of Safety Integrated when the drive bus fails (from SW 6.4.15)
required is read-in from the DMP modules on the drive bus, then the response
time for an Emergency Stop – that almost always occurs simultaneously with a
bus failure, increases by the time specified in
$MN_SAFE_PULSE_DIS_TIME_BUSFAIL. The pulses are only cancelled after
this time and the initiated Emergency Stop is not recognized. This is the
reason that $MN_SAFE_PULSE_DIS_TIME_BUSFAIL must be selected to be
relatively short. In situations such as these, we recommend that the local inputs
on the NCU or PROFIsafe are used.
When DMP modules are used on the drive bus with local inputs on the NCU or
F-DI modules with PROFIsafe, the engineer programming the SPL must take
into account this different behavior if he wishes to configure a delayed pulse
cancellation when the drive bus fails.
$A_OUTSE The $A_OUTSE system variables include the outputs of the NCK-SPL, that
should be output to the peripherals. The output/outputs to terminal 663 of the
terminal module must be output via the local outputs on the NCU. Under no
circumstances may these outputs be output via the DMP modules connected to
the drive bus as this would result in immediate pulse cancellation if the drive
bus was to fail.
$A_INSI $A_INSI is the input interface to the axial NCK monitoring functions. This
means that it includes the NCK-SGA. The NCK-SGA are left in their old state
so that when the drive bus fails, no further action is require here.
$A_OUTSI $A_OUTSI is the output interface to the axial NCK monitoring functions. This
means that it includes the NCK-SGE. In this interface, only the SGE "de-
selection of the external STOP A", "SBH selection" and the selection of an SG
stage for personnel protection are relevant (also refer to "behavior of the axial
NCK monitoring channel"). The reason for this is that the actual axial monitoring
functions are no longer active:
•
•
3.13.4 Behavior of the drive monitoring channel
The drive monitoring channel delays, just like the NCK monitoring channel, its
pulse cancellation by the parameterized time. However, in addition, it keeps the
monitoring functions active that were active at the instant of the failure. The
drive can still monitor as it still has access to the correct actual value.
In the following cases, when the drive bus fails, the pulses are immediately
cancelled – even if a delay time has been parameterized:
•
•
3-200
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
An external stop with low priority cannot be executed as setpoints cannot
be transferred to the drive.
The additional axial NCK monitoring functions required the actual value
that is no longer available.
The SBH function is selected.
An SG stage has been selected where it has been previously defined, that
in this SG stage, no ESR should be executed when the drive bus fails (e.g.
SG stage for personnel protection).
© Siemens AG 2003 All Rights Reserved
11.03