Rockwell Automation 1769-HSC Compact High Speed Counter Module - Manual (Page 60)

60 Rockwell Automation Publication 1769-UM006E-EN-P - July 2013
Chapter 3 Installation and Wiring
Figure 15 - Single-ended Encoder Wiring
(1)
Refer to your encoder manual for proper cable type. The type of cable used should be twisted-pair, individually
shielded cable with a maximum length of 300 m (1000 ft).
(2) External resistors are required if they are not internal to the encoder. The pull-up resistor (R) value depends on
the power supply value. The table below shows the maximum resistor values for typical supply voltages. To
calculate the maximum resistor value, use the following formula:
where:
R = maximum pull-up resistor value
VDC = power supply voltage
Vmin = 2.6V DC
Imin = 6.8 mA
The minimum resistor (R) value depends on the current sinking capability of the
encoder. Refer to your encoder’s documentation.
Power Supply Voltage (V DC) Pull-up Resistor Value (R), Max (1)
(1) Resistance values can change, depending upon your application.
5 352

12 1382

24 3147

A
B
Z
A1(+)
A1(–)
B1(+)
B1(–)
Z1(+)
Z1(–)
GND
VS +VDC
COM
R
(2)
Cable (1)
Power
Supply
Allen-Bradley
845H Series
Single-ended
Encoder
Shield/Housing
Connect only if housing is electronically
isolated from the motor and ground.
Shield
Module Inputs
Earth
R
VDC Vmin
–
Imin
-------------------------------------------- =