Document Number: P-SS-004-09 Rev 5
Old Numbers (AS6007H, A-SS-004-20208)
Revised 11/20/2003
www.DanaherMotion.com
Page
13
Whether you use the
Gearing
dialog box or the terminal window, you can set the encoder
resolution only to one of eight values: 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, and 65536.
If your encoder has non-binary resolution (for example, 1000 lines/revolution), select the resolution
closest to your encoder. You can adjust the gear ratio to correct for the difference of the selected
value and the actual resolution.
Selecting the Gear Ratio
The gear ratio is defined by the ratio of two variables, GEARI and GEARO. This allows the
accurate entry of non-integer ratios, such as 1:3. To understand how GEARI and GEARO set the
ratio, imagine a pair of gears with the number of teeth on each gear defined by these variables. The
gear ratio is:
VELOCITY
SLAVE
= VELOCITY
MASTER
*
(GEARI / GEARO.)
The units of velocity are RPM. The values of GEARI and GEARO are somewhat arbitrary because
the gear ratio is set by the ratio of these two variables. For example, setting GEARI and GEARO to
the same values generates 1:1 gear ratio.
To set the gear ratio, type the ratio in the two text boxes at the right part of the
Gearing
dialog box
(Figure 15). The example in Figure 15 shows the settings for a gear ratio of 1:2 (
GEARI = 1
and
GEARO = 2
), assuming the input encoder resolution (ENCIN) is
512
lines/revolution. In Figure 15,
the window displays the gear ratio in counts by calculating it from ENCIN, GEARI, and GEARO.
In this example,
512
Pulses
from the input encoder generates a command equal to one revolution,
as shown at the bottom of the
Gearing
dialog box.
Figure 15: Setting the Gear Ratio
