Siemens SINUMERIK 828D Function Manual page 1627

DB31, ...
DBX1.3 Axis/spindle disable
Special cases, If, for an axis/spindle "axis/spindle disable" is present, then the interface signals:
errors, .... DB31, ... DBX2.1 (controller enable),
DB2 ... (feed/spindle stop)
and where relevant
DB31, ... DBX12.0-12.1 (hardware limit switch)
are not effective regarding braking the axis/spindle.
The axis/spindle can however be brought into the "follow up" or "hold" state
(refer to DB31, ... DBX1.4 (follow­up mode)).
Notes:
This signal inhibits setpoint output to the drive.
A brief pulse can bring a traversing axis to a standstill. The axis will not move again in this block, but
only when the next block is reached.
Re­synchronization takes place automatically on the next traversing command for this axis, i.e. the
axis traverses the remaining distance­to­go.
For response together with synchronized operation, see:
References:
/FB2/ Function Manual Expanded Functions; Synchronized Spindle (S3)
This signal is no longer effective when the coupling for FS/FA is activated. → No. 6
If the signal for the LS/LA is set, it also applies to the FS/FA(s) → No. 7
A workpiece clamped between two spindles (workpiece transfer from front to rear­side machining)
cannot be destroyed.
Corresponding to ... DB21, ... DBX33.7 (program test active)
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Z1: NC/PLC interface signals
19.1 Various interface signals and functions (A2)
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