Siemens SINUMERIK 840D Description Of Functions page 70

3 Safety-Related Functions
3.1 Basic mechanisms of SI functions
Description of STOP A Action in the drive monitoring channel:
Pulses are immediately cancelled using the internal signal "cancel pulses". In
addition, the pulses in the gating unit are cancelled by a software function.
Action in the drive monitoring channel:
Pulses are cancelled via the SGA "enable pulses".
•
•
•
SGA STOP A/B is active
This signal is used to indicate that STOP A/B is active.
0 signal:
1 signal:
Description of STOP B Action in the drive and NCK monitoring channels:
The drive is braked along the current limit as the result of a 0 speed setpoint
that is input instantaneously either directly or from the NCK via the drive bus.
Action in the drive monitoring channel:
If the speed actual value drops below the value set in
$MD_SAFE_STANDSTILL_VELO_TOL or if the timer set in
$MD_SAFE_PULSE_DISABLE_DELAY has expired, the stop mode changes
automatically to STOP A.
Action in the drive monitoring channel:
Essentially the same as in the drive channel, the stop mode changes
automatically to STOP A when the actual speed drops below the value in
$MA_SAFE_STANDSTILL_VELO_TOL or after the timer set in
$MA_SAFE_PULSE_DISABLE_DELAY has expired.
•
•
•
SGA STOP A/B is active
This signal is used to indicate that STOP A/B is active.
0 signal:
1 signal:
3-70
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
Effect:
The drive coasts to a standstill if no external braking mechanism such as
an armature short-circuit and/or holding brake is used. The axis-specific
alarm results in a mode group stop, i.e. as the result of the error in one
axis, all axes and spindles in a mode group are stopped. "Safe standstill"
becomes operative at the end of STOP A.
Alarm message:
The alarm message "STOP A triggered" is displayed.
Acknowledgement:
An unintentional restart is prevented for STOP A. The error can only be
acknowledged from the drive and control with power on.
STOP A/B is not active
STOP A/B is active
Effect:
The drive is braked along the current limit under speed control and finally
brought to a safe standstill.
Alarm message:
The alarm message "STOP B triggered" is displayed.
Acknowledgement:
An unintentional restart is prevented for STOP B. The error can only be
acknowledged from the drive and control with power on.
STOP A/B is not active
STOP A/B is active
© Siemens AG 2003 All Rights Reserved
11.03