Rockwell Automation 1769-L23E-QB1B_L23E-QBFC1B_L23-QBFC1B CompactLogix Packaged Controllers Quick Start and User Manual - Manual (Page 210)

210 Publication IASIMP-QS010B-EN-P - October 2009
Chapter 3 Embedded I/O
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, use the following formula:
where:
R = maximum pull-up resistor value
Vdc = power supply voltage
Vmin = 2.6V dc
Imin = 6.8 mA
Resistor Values for Supply Voltages
Power Supply Voltage Pull-up Resistor Value (R), max
(1)
(1) Resistance values may change, depending upon your application.
The minimum resistor (R) value depends on the current sinking capability of the sensor. Refer to your sensor’s
documentation.
5V DC 352
Ω
12V DC 1382
Ω
24V DC 3147
Ω
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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