Master-Slave 06/2005 Danaher Motion
For optimal performance, the master axis should have an axis number less
than the slave axis. If the slave axis is A1 and the master axis is A2, an
additional time cycle is inserted in the motion.
If the master velocity override is changed, the slave velocity is changed
accordingly. In a relative move, the slave moves according to its new velocity
override. VELOCITYOVERRIDE has no effect on the master signal for a
slaved axis. It also has no effect on the gear ratio or cam table.
VELOCITYOVERRIDE modifies the velocity of incremental moves added
onto geared or cammed motion.
5. 2 GEARING
When two axes are geared, the position command of the slave is
proportional to the master signal as shown below.
Gearing works in both directions of master travel. The term, proportional, is
applied loosely. The offset between the master and slave axes is saved at
the time gearing is enabled and is maintained throughout gearing.
5.2.1. Enable Gearing
To enable gearing, set MASTERSLAVE to GEAR:
A1.Slave = GEAR 'Enable gearing
Enabling gearing during an absolute or relative move generates an error. An
error is also generated if an attempt is made to enable gearing during
camming. Incremental moves are allowed when gearing is enabled and
during gearing.
5.2.2. Disable Gearing
To disable gearing, set SLAVE to OFF:
A1.Slave = OFF 'Disable gearing
When gearing is disabled, the velocity of the slave axis is decelerated to zero
at the rate of <axis>.DECELERATIONMAX (DMAX). Disabling an axis
does not automatically disable gearing. You do not need to enable gearing
again when the axis is re-enabled. However, issuingJOG or STOP for the
axis disables gearing.
STOP turns gearing off immediately. The velocity of the axis is decelerated to
zero at the rate set by <axis>.DMAX. For JOG, gearing is disabled
immediately and the movement is controlled by the JOG profile.
If the master axis' RTK (RealTime Kernel or software code) is executed
before the slaves’ RTK, (i.e., if ?axislist displays the master before displaying
the slave) and the master source is PCMD, there is no delay in execution. If
the master source is a feedback, PFB or PEXT, there is a system delay of 1
SERCOS cycle time. If the slave RTK is executed before the master RTK, an
additional delay of 1 cycle time is incurred.
106 Rev E M-SS-005-03l
