Rockwell Automation Publication 2080-UM004C-EN-E - March 2015 29
High Speed Counter – 2080-MOT-HSC Appendix 4
Quadrature Counter (X1)
The module is compatible with 2 and 3 signal quadrature, or incremental
encoders. The A and B signals are offset by 90 degrees and encode the direction of
the rotation. The third signal, Z, occurs once per revolution and is often used as a
home reference. The module’s use of this signal is discussed below in the Z input
section.
INPUT A
INPUT B
INPUT Z
Increment Pulse
(Input A)
Count Pulse
(Input A)
1
2
3
2
1
0 0
1
Increment Pulse
(count up)
Decrement Pulse
(count down)
Incrementing
Encoder or Sensor
Decrementing
Encoder or Sensor
Present Count
Up/Down Counting
A B Change in Count Value
0 or 1 +1
0 or 1 -1
0
00 0