Delta RMC101 - Manual (Page 190)

RMC100 and RMCWin User Manual
4-4
In the Mode command parameter, do the following:
• Set the Gear Bit (bit 12, 0x2000 hex). If this bit is not set, then the Go command will not initiate
a geared move. It will instead do a point-to-point or speed control move.
• Use the Gear Master Select bits (bits 4-6) to select the desired master axis. Multiple slaves
can be geared to the same master.
• Set the Gear Type Bit (bit 14, 0x4000 hex) to be geared to the master's Actual Position. Clear
this bit to gear to the master's Target Position.
2. Specify the Gear Ratio.
The slave-to-master gear ratio is specified by the Command Value command parameter divided by
the Speed command parameter, as shown in the below three equivalent equations:
* The master speed and position used may be based on either the Actual or Target Position, as
selected by the Gear Type bit in the Mode word.
Note: When the gear ratio is clutched between two ratios--such as from non-geared to 2:5 gearing--
the gear ratio will be ramped at a user-specified rate (see below). This clutching will take place by
ramping the gear ratio numerator from its original value to the final ratio numerator. However, the
interim numerator values must always be integers. Therefore, it is recommended that relatively large
values be used for the gear ratio components. For example, instead of specifying values of 2 and 5
for a 2:5 ratio, you might specify 2000 and 5000. This allows clutching through up to 2000 gear ratios
instead of only two, for a much smoother clutch.
Example:
To obtain a gear ratio of 1:2, such that the slave axis moves at half the speed of the master axis, you
will enter a Command Value that is one half the value of the Speed. A Command Value of 1000, and
a Speed of 2000 would work. As described in the above note, values of 1 and 2 would also work, but
there would be no clutching: the axis would go directly from a 0:2 to a 1:2 gear ratio. By using the
equivalent 1000:2000 gear ratio, clutching from 0:2000 to 1000:2000 can be made in up to 1000
small gear steps.
3. Specify the Gear Ratio Clutching.
Whenever a Gear command is given to an axis that is already geared, the gear ratio is ramped from
the current ratio to the requested ratio. Unless the gear ratio is ramping to or from zero, only the
numerator (given in the Command Value command parameter) can change; the denominator (given