Omron Sysmac NX Series User Manual page 98

4 Installation and Wiring
Two-wire sensor
The voltages and currents related to the conditions for PNP type sensors are shown in the figure
below.
Two-wire sensor
V : Power supply voltage
CC
V : Sensor's output residual voltage
R
V : OFF voltage at trigger input of the High-speed Analog Input Unit
OFF
I : Sensor leakage current
leak
R: Bleeder resistor
I : OFF current at trigger input of the High-speed Analog Input Unit
OFF
 Precautions on Sensor Inrush Current
An incorrect input may occur due to sensor inrush current if a sensor is turned ON after the High-
speed Analog Input Unit has started up to the point where inputs are possible.
Determine the time required for sensor operation to stabilize after the sensor is turned ON, and
take appropriate measures, such as inserting an ON delay into the user program after turning ON
the sensor.
A programming example is shown below.
The sensor's power supply voltage is used as the input bit to Sensor_power.
4 - 30
IOV
IOG
IOV
R
V V
I
I
CC OFF
leak
OFF IN
V
R
IOG
IOV
IOG
IOV
V V
R CC
I
I
leak IN
OFF
V
R
OFF
IOG
NX-series Analog I/O Units User's Manual for High-speed Analog Input Units (W592)
Unit that can supply I/O power
to the NX bus
High-speed Analog Input Unit
Unit that can supply I/O power
to the NX bus
High-speed Analog Input Unit