Rockwell Automation 8720MC High Performance Drives Installation Manual - Manual (Page 56)

Publication 8720MC-IN001D-EN-P — December 2002
2-22 8720MC Connector Data
Understanding Analog
Interface Connections A quad B Virtual Encoder Output
A virtual 1024 line encoder output interface is provided for use with
any motion controller which provides an analog velocity or torque
command and expects a 5V TTL A quad B signal from the motor. The
quadrature outputs are connected to P5-1, P5-2, P5-3, P5-19, P5-20
and P5-21, as shown in Appendix B.
Figure 2.19 shows the exact nature of the A quad B signals. If the
quadrature output signals are required, the SNS-60 (8720SM S3, S4)
Sincoder must be the 8720SM motor feedback device. The marker
from this feedback device has a random width from encoder to
encoder. The edge rise is repeatable for any given encoder. This
feedback device is best suited for uni-directional homing and
referencing. The 8720MC provides the 5V dc power required to drive
the signals. Connect the motion controller encoder ground terminal to
the P5-4 terminal (ACOM). This assures that the signals are properly
referenced to the motion controller encoder ground. The motion
controller will count square wave edges and will achieve a 4096 count
per turn resolution.
Figure 2.19
A quad B Output
For connections to the encoder output use 4 twisted pair, #22 AWG or
larger, shielded cable, Beldon 8304 or equal. A special multiplier box
is available for the Stegmann encoders. This multiplier box can be
used to simulate a 5120 lines per revolution virtual encoder. In this
instance the motion controller will also count square wave edges but
will achieve a 20480 count per turn resolution. For details contact your
Rockwell Automation Motion Application Engineer.
0 VDC
5 VDC
0 VDC
0 VDC
5 VDC
5 VDC
A Channel
B Channel
1024 lines/revolution
1024 lines/revolution
Reference 90 DEG minimum marker
630 DEG
maximum marker
A quad B output