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Rockwell Automation Publication 2198-UM002E-EN-P - February 2018
Chapter 4
Connector Data and Feature Descriptions
Encoder Phasing Definitions
For TTL encoders, the drive position increases when A leads B. Clockwise
motor rotation is assumed, when looking at the shaft.
Figure 52 - TTL Encoder Phasing
For Sin/Cos encoders (Stegmann Hiperface and Heidenhain EnDat), the drive
position increases when Cosine (B) leads Sine (A). Clockwise motor rotation is
assumed, when looking at the shaft.
Figure 53 - Sine/Cosine Encoder Phasing
A
/A
90°
90°
90°
90°
360°
B
/B
Z
/Z
B
A
IMPORTANT
The Sine/Cosine encoder signal phasing is different than the TTL encoder
signal phasing.
IMPORTANT
When using a Sine/Cosine feedback device, the drive cannot synthesize a
marker signal, so a physical marker signal is required for the home-to-
marker sequence (and the marker hookup test) to complete.
When using absolute feedback devices (for example, Stegmann
Hiperface) the drive synthesizes a marker signal because these devices
don't have a marker signal required for the home-to-marker sequence
(and the marker hookup test) to complete.