Description Of Stop D - Siemens SINUMERIK 840D sl Function Manual

Safety Functions Integrated in the System/Drive
6.3 Safe Stops A–F
S Effect:
The drive is braked along the STOP2 ramp under closed–loop speed control
and brought into SBH.
S Alarm message for an internally initiated STOP C:
The alarm message "STOP C initiated" is output (see Chapter 10.2, "Alarms for
SINUMERIK 840D sl").
S Acknowledgement for an internally initiated STOP C:
An unintentional restart is prevented for a STOP C. The error can be acknowl-
edged using the NC–RESET key.
SGA STOP C is active
This signal indicates that STOP C is active.
0 signal:
1 signal:
It is possible that the stop for the NCK becomes effective one safety monitoring
clock cycle earlier than for the drive. This means that braking along the current
limit can become effective before the STOP2 ramp of the drive becomes effective.
In order to reduce the level of stress of the mechanical system of the machine (if
required) the braking torque can be reduced. To realize this, bit 4 "Torque limiting
active in motoring/regenerating mode" can be set in parameter p1400 and parame-
ter p1521 "Torque limit lower/regenerative" can be set to the required lower torque.
In this case, it should be noted that the braking distance (stopping distance) of the
axis is extended.
SGE deselect external STOP C
If a stop request is active, SGA "STOP C is active" is set in the same way as it
would be for an internally initiated STOP C.
MD 36977: $MA_SAFE_EXT_STOP_INPUT[1] is used to define the selection/de-
selection of the external braking request; in this case "deselect external STOP C"
(braking along the current limit).
6.3.5

Description of STOP D

Action in the drive monitoring channel:
The drive monitoring channel requests a path stop or braking along the actual ac-
celeration characteristic. In parallel, the timer is started via parameter 9553: "tran-
sition time from STOP D to SBH" is started. The SBH function is automatically acti-
vated after the timer expires.
Action in the NCK monitoring channel:
Essentially the same as the drive, the control system monitoring channel requests
a path stop or braking along the acceleration characteristic. At the same time, the
timer via MD 36953: $MA_SAFE_STOP_SWITCH_TIME_D is started. The SBH
function is automatically activated after the timer expires.
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SINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) – 05.2008 Edition
STOP C is not active.
STOP C is active.
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05.08