Rockwell Automation 1769-L23E-QB1B_QBFC1B_QBFC1B CompactLogix Packaged Controller Installation Instructions - Manual (Page 26)

26 CompactLogix Controller
Rockwell Automation Publication 1769-IN082C-EN-P - February 2013
HSC Discrete Device Wiring
(1) External resistors are required if they are not internal to the sensor. 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, 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 sensor. Refer to
your sensor’s documentation for more information.
Power Supply Voltage (VDC) Maximum Pull-up Resistor Value (R) (1)
(1) Resistance values may change, depending upon your application.
5V DC 352

12V DC 1382

24V DC 3147

VS
A1(+)
A1(–)
B1(+)
B1(–)
Z1(+)
Z1(–)
+VDC
COM
VS
OUT
COM
OUT
COM
VS
OUT
COM
R
(1)
Power
Supply
Module Inputs
Solid-state
Switch
Proximity Sensor
Photo-electric Sensor with Open
Collector Sinking Output
R
V DC Vmin –  
Imin
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