11.03
3 Safety-Related Functions
3.1 Basic mechanisms of SI functions
© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
3-65
The state of the active monitoring function (SBH, SG, SE, SN) is not changed
by "test stop external shutdown".
Since the SGE "status pulses cancelled" is only used for checking pulse
cancellation for test stop or for "test stop external shutdown", this signal can be
configured according to the 3-terminal principle. In this way, the information for
all 611 digital modules no longer has to be obtained by wiring the AS1/AS2
terminals to NCK I/Os. The 3-terminal principle is used in the form of a two-
channel pulse-cancellation control with single-channel feedback.
The function is activated by configuring the SGE "status pulses cancelled". Up
to now, the assignment to an I/O input or to the NCK-SPL had to be made via
MD $MA_SAFE_PULSE_STATUS_INPUT. If this machine data is set to 0, the
information on whether or not the pulses have been cancelled is retrieved from
the SI interface of the 611 digital.
The test stop is executed internally in the drive monitoring channel (via the
NC/PLC interface). To implement the test stop for the NCK monitoring channel,
the SGEs/SGAs must be appropriately connected-up for each axis.
A large number of inputs and outputs are required in the NCK when there are
several axes. It is possible to group or distribute signals using inputs/outputs
assigned via machine data (refer to Chapter 4, "Data description").
To obtain the "test stop selection" signal of a certain axis, it must be possible to
evaluate the checkback signal "pulses cancelled status" for the same axis in
order to be able to detect if there are any errors.
For a dual-axis module, there is only one terminal 663 and one AS1/AS2 for
both axes. The shutdown path in the NCK and drive monitoring channels must
still be tested in succession for both axes.
The following example (refer to Fig. 3-6, "Testing the shutdown path") shows a
circuit for testing the shutdown path of the NCK with four axes, axes 3 and 4
being provided by a dual-axis module.
Checkback signals,
pulse cancellation
(SW 6.3.21 and higher)
Activation
Testing the shutdown
paths for several axes
without SPL
Testing the shutdown
paths for a dual-axis
module