Safely-Reduced Speed When Using Selector Gearboxes - Siemens SINUMERIK 840D Description Of Functions

11.03
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3.5.3

Safely-reduced speed when using selector gearboxes

Using selector The following points must be noted for spindles with selector gearboxes.
gearboxes
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© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
Effect of the function in the NCK interpolator:
- Setpoint limiting is active in both AUTO and JOG modes.
- When changing over when traversing/moving to higher safely-reduced
speeds, the position control loop should be set so that it does not
overshoot, so that a sudden setpoint limit change does not cause
the monitoring to respond on the actual value side.
- When transformation is active, safety setpoint limits, axially effective in
the interpolator are reduced by the transformation itself depending
on the actual position.
Note
There are no restrictions for motion from synchronous actions.
When a 1-encoder system is used, gear ratios (gear stage selection) must
be selected via two channels (refer to Chapter 3, "Example of application
for safe sensing of gear ratios").
The user agreement (if set) is canceled during a gear change and the SGA
"axis safely referenced" set to "0". When the gearbox stage is selected via
PLC and/or by selecting a new ratio, a gear shift is detected using SGEs.
The spindle must be re-synchronized after a gear change.
The user must bring the spindle into the "axis safely referenced" state if the
"safe cams" function is used.
The value for the actual value comparison tolerance (crosswise) must be
set higher than the oscillation actual value when in the oscillation mode.
For 840D MD 36942:
For 611 digital MD 1342:
When changing over from a high to a lower speed limit value, a delay timer
is started. While this timer is running, the speed is monitored for violation of
the last valid speed limit value. When changing-over from a low to a high
speed limit value, the higher limit becomes effective immediately.
3 Safety-Related Functions
3.5 Safely-reduced speed (SG)
$MA_SAFE_POS_TOL
$MD_SAFE_POS_TOL
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