E3X-DA11-N Datasheet, PDF (32/36 Pages) Omron Electronics LLC – The Ultimate Fiber Amplifier for Maximum Ease of Use and High Performance

Photoelectric Sensors Technical Guide
Noise
Countermeasures for noise depend on the path of noise entry, frequency components, and wave heights. Typical measures are as given in the
following table.
Type of noise
Noise intrusion path and countermeasure
Before countermeasure
After countermeasure
Noise enters from the noise source through the frame
(metal).
Common mode noise
(inverter noise)
Common noise
applied between the
mounting board and
the +V and 0-V
lines, respectively.
Sensor
Mounting block
(metal)
+V ^Inverter
motor
0V
IM
Noise
(1) Ground the inverter motor (to 100 Ω or less)
(2) Ground the noise source and the power supply (0-V
side) through a capacitor (film capacitor, 0.22 μF, 630
V).
(3) Insert an insulator (plastic, rubber, etc.) between the
Sensor and the mounting plate (metal).
Insert an insulator.
Sensor
(3)
(2)
+V _{Inverter motor}
0V
Noise
Noise ^IM
Mounting block
(metal)
Noise ⁽¹⁾
Radiant noise
Ingress of high-fre-
quency electromag-
netic waves directly
into Sensor, from
power line, etc.
Noise propagates through the air from the noise source
and directly enters the Sensor.
Noise
source
+V
Sensor
0V
• Insert a shield (copper) plate between the Sensor and
the noise source e.g., a switching power supply).
• Separate the noise source and the Sensor to a distance
where noise does not affect operation.
Noise
source
Shield plate (copper)
+V
Sensor
0V
Noise enters from the power line.
Power line noise
Ingress of electromag-
netic induction from
high-voltage wires
and switching noise
Noise
+V
Sensor
Noise
0V
from the switching
power supply
• Insert a capacitor (e.g., a film capacitor), noise filter (e.g.,
ferrite core or insulated transformer), or varistor in the
power line.
Sensor
Insert a capacitor, etc.
+V
Noise
0V
● Wiring
Cable
Unless otherwise indicated, the maximum length of cable extension is
100 m using wire that is 0.3 mm² or greater.
Exceptions are indicated in Safety Precautions in individual product
information.
Cable Tensile Strength
When wiring the cable, do not subject the cable to a tension greater than
that indicated in the following table.
Cable diameter
Less than 4 mm
4 mm or greater
Tensile strength
30 N max.
50 N max.
Note: Do not subject a shielded cable or coaxial cable to tension.
Repeated Bending
Normally, the Sensor cable should not be bent repeatedly.
(For bending-resistant cable, see Attachment to Moving Parts on
page C-4.)
Separation from High Voltage (Wiring Method)
Do not lay the cables for the Sensor together with high-voltage lines
or power lines. Placing them in the same conduit or duct may cause
damage or malfunction due to induction interference. As a general
rule, wire the Sensor in a separate system, use an independent metal
conduit, or use shielded cable.
Power line
Work Required for Unconnected Leads
Unused leads for self-diagnosis outputs or other special functions
should be cut and wrapped with insulating tape to prevent contact with
other terminals.
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C-3