Stopping As Autonomous Drive Function - Siemens SINUMERIK 840C Installation Instructions Manual

09.95
Existing GI and IKA link branches with simulated leading axes/input quantities are not cancelled
until T2 has expired.
Continued traversal as an interpolative process is desirable to suppress the brief synchronism
deviation (break in speed curve) which occurs on transition to braking mode. It is particularly
important to eliminate this effect during finishing cut processes.
While the traversal motion continues, the positive connection between the tool and workpiece
is separated independently of the stop operation if "Retraction" is programmed and enabled.
Note:
The total time T1 + T2 + T3 should not exceed a maximum value (e.g. 1 second) for safety
reasons. The user is responsible for observing this maximum value.
12.20.6.2

Stopping as autonomous drive function

• This new, extended autonomous drive stop operation is intended to ensure that the drives
of a previously linked GI grouping can be stopped as simultaneously as possible if this
cannot be implemented in the control system.
• The function must be enabled via a general machine data NC-MD 5022, bit 1 (extended
stopping) and via a source-related machine data NC-MD 529*/592* (channel-specific or
axis/specific autonomous drive ESR).
The following reaction can be programmed:
• The speed setpoint currently active when the error occurs continues to be output for time
T1 (diagram: parameterizable/programmable stop operation as open-loop control function).
The purpose of this is to maintain the motion which was being executed before the failure
until the positive connection has been separated or until the retraction operation initiated in
parallel in other drives has been executed. This may be purposeful for all leading/following
drives, or for linked drives, or for drives operating in a grouping.
• On expiry of time T1, all axes are stopped at the current limit through injection of a zero
setpoint; pulse suppression is initiated as soon as the axes have stopped.
Note:
In contrast to stopping as an open-loop control function, it must be noted that this function
affords nothing more than an autonomous drive reaction, i.e. it is not possible to control an
interpolation grouping of several axes on an interpolative basis nor is it possible to control,
brake or make follow an axis link on a closed-loop control basis.
© Siemens AG 1992 All Rights Reserved
SINUMERIK 840C (IA)
6FC5197- AA50
12 Functional Descriptions
12.19.6 Stopping
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