Siemens SINUMERIK 840D sl Function Manual page 437

● The following VDI signals remain set at 1:
By using the machine data:
MD11410 $MN_SUPPRESS_ALARM_MASK (mask for suppressing special alarms) (BIT20)
the alarm 2900 is suppressed, however, the NCK triggers the same reactions.
As alarm 2900 deactivates the axis position control, this alarm must be configured to effect
application of the mechanical brakes by the PLC. Rebooting the PLC forces the PLC outputs
to change to defined zero. The brakes must be connected up in such a way that they remain
closed at zero, i.e. a 1 signal on the PLC allows the brakes to open.
Note
In terms of its reactions, the alarm is the same as the Emergency Stop alarm (3000). For
internal reasons, the reboot delay time of the NCK can be slightly increased.
Activation
The reboot management is activated when the following machine data is set to a value other
than zero:
MD10088 $MN_REBOOT_DELAY_TIME (reboot delay)
Evaluation with a system variable
System variable $AN_REBOOT_DELAY_TIME can be read in a synchronized action. A
value higher than zero indicates that the reboot request initiated by the HMI has been issued
and how much time (in seconds) the NCK will allow until reboot (Power Off followed by
Power On). The user can detect an imminent reboot by reading a synchronized action and
react accordingly (e.g. with "Safe Standstill" in a Safety Integrated application).
$AN_REBOOT_DELAY_TIME is 0.0 as long as the HMI has not initiated a reboot request.
See also:
/PGA1/ List of System Variables.
Extended Functions
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
For further details, see machine data:
MD36610 $MA_AX_EMERGENCY_STOP_TIME (braking ramp time when errors occur)
and
MD36620 $MA_SERVO_DISABLE_DELAY_TIME (switch-off delay controller release)
Note
The NCK deactivates the position control after SERVO_DISABLE_DELAY_TIME.
DB10 DBX108.7 (NC ready)
5.9 Electronic weight compensation (vertical axis)
Compensations (K3)
437