Rockwell Automation 1771-IJ_IK IK ENCODER/COUNTER MODULES - Manual (Page 19)

2–7 Preliminary Adjustments
Publication 1771ĆUM006B-EN-P - June 2002
No special filtering is provided on channel B, since the filtering
necessary for a mechanical switch would defeat the purpose of a very
fast count direction change that is not dependent on the processor
scan time. Therefore, a transistor switch or gate should be used to
pull the channel B input low, sinking 10mA at 12V dc or 20mA at
24V dc. The count changes direction in less than 10 microseconds
from the time channel B input changes state.
Refer to the connection diagrams (Figures 3.1 and 3.2) for
interfacing different devices.
Switch assembly settings-these features are selected on two switch
assemblies that are located on the circuit board underneath the
component cover.
To select these options, proceed as follows:
1. Take off the left-side cover by removing the four slotted screws.
2. Refer to Figure 2.3. Identify the programming option switch
assembly (SW-1) and the input configuration switch assembly
(SW-2).
Figure 2.4
Location ofSwitch Assemblies
159 47
O
N
O
F
F
O N O F F
Input
Configuration
Switch
Assembly SWĆ2
Programming
Options
Switch
Assembly SWĆ1
Setting Switch Assemblies