Siemens SINUMERIK 840D Function Manual page 853

Coupling characteristics
The following characteristics can be defined for every synchronous spindle coupling:
● Block change behavior
The condition to be fulfilled for a block change can be defined on activation of synchronous
operation or on alteration of the transformation ratio or the defined angular offset when the
coupling is active:
– Block change takes place immediately
– Block change in response to "Fine synchronism"
– Block change in response to "Coarse synchronism"
– Block change for IPOSTOP (i.e. after setpoint-end synchronism)
– Check of the synchronism conditions at an arbitrary moment with WAITC.
● Type of coupling between FS and LS
The position setpoint or the actual position value of the leading spindle can be used as the
reference value for the following spindle. The following coupling types can therefore be
selected:
– Setpoint coupling (DV)
– Actual value coupling (AV)
– Speed coupling (VV)
The selection of the relevant coupling characteristics for the configured coupling is made using
machine data (see Section "Configuration (Page 871)") and for the user defined coupling
using the COUPDEF language command (see Section "Definition (COUPDEF) (Page 865)").
In addition, coupling characteristics Type of coupling and Block change response can be
altered for the permanently configured coupling by means of language command COUPDEF.
Further information
Programming Manual Advanced Synchronous spindle
Change protection for coupling characteristics
The channel-specific MD21340 $MC_COUPLE_IS_WRITE_PROT_1 is used to define whether
or not the configured coupling parameters Transformation ratio, Type of coupling and Block
change response can be altered by the NC part program:
0: Coupling parameters can be altered by the NC part program via command COUPDEF
1: Coupling parameters cannot be altered by the NC part program. Attempts to make changes
will be rejected with an alarm message.
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
Use in position controlled operation. The control dynamic response of both spindles
should coincide as far as possible. Preferably, the setpoint coupling should be used.
Application if no position control of the LS is possible or with great deviation of the control
characteristics between FS and LS. The setpoints for the FS are derived from the actual
values of the LS. The quality of synchronism is worse with a varying spindle speed than
with the setpoint coupling.
Internally, the velocity coupling is a setpoint coupling. The requirements for FS and LS
are lower. Position control and measuring systems are not required for FS and LS.
The position offset between FS and LS is undefined.
S3: Synchronous spindle
19.1 Brief description
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