Delta RMC101 - Manual (Page 212)

RMC100 and RMCWin User Manual
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4.9 Synchronizing Axes
Axis synchronization is achieved by setting either the Sync A or Sync B bit in the MODE word on
the axes to be synchronized and then issuing a Go or Relative Move command to the last axis in
the sync group. Up to two groups of axes can be synchronized together. If both groups are used,
then one group must use the Sync A bit, and the other uses Sync B. Each group can contain as
many axes as desired.
The following requirements exist when synchronizing a group of axes:
• All synchronized axes must be initialized, as indicated by the Parameter Initialized bit in the
STATUS word. Do this by issuing the Set Parameters command.
• The low eight MODE bits of each synchronized axis must match exactly.
• Synchronized commands (Go and Relative Move) must be issued to the last synchronized axis.
The last synchronized axis is the highest numbered axis in the group and is displayed in the
right-most column in RMCWin.
• Synchronized commands issued to any synchronized axis other than the last axis are ignored.
• The MODE, ACCELERATION, DECELERATION, SPEED, and COMMAND VALUE fields must
be set in all axes to be synchronized before any synchronized commands are issued.
Internal to the RMC, the synchronization is accomplished as follows:
• For each group of axes the axis with the longest travel distance is designated the master. If two
or more synchronized axes tie for having the longest travel distance, then the first of those axes
is designated the master. The other synchronized axes are designated as slaves.
• The maximum speed of the master axis is limited so none of the synchronized axes will go
above their requested SPEED.
• The master then moves toward its destination using its own ACCELERATION,
DECELERATION, and the speed calculated in the above step.
• At the same time, the TARGET POSITIONS of the slave axes are ratioed to the target position
of the master based on the distance each is traveling.
• If any synchronized axis is halted during the move, all the other axes will halt as well.
• If a new Go or Relative Move command is given to a slave axis which changes or removes the
Sync bit used in the MODE word, then that slave will perform the new move, and all of the axes
it was previously synchronized with will continue their synchronized move.
• If a new Go or Relative Move command is given to the master axis which changes or removes
the Sync bit used in the MODE word, then the master will perform the new move, but all of its
previous slaves will stop.
• If a new Go or Relative Move command is given to the last synchronized axis which retains the
Sync bit in the MODE word, then all synchronized axes will start a new move from their current
positions.