Reducing Electrical Noise - Omron CJ - 09-2009 Operation Manual

Wiring
5-3-5

Reducing Electrical Noise

I/O Signal Wiring
Inductive Loads
276
Method 1
Add a resistor that draws about 1/3 of the current consumed by the bulb.
Method 2
Add a control resistor as shown in the following diagram.
Whenever possible, place I/O signal lines and power lines in separate ducts or
raceways both inside and outside of the control panel.
Suspended duct
If the I/O wiring and power wiring must be routed in the same duct, use
shielded cable and connect the shield to the GR terminal to reduce noise.
When an inductive load is connected to an I/O Unit, connect a surge suppres-
sor or diode in parallel with the load as shown below.
L Diode
COM
OUT
Relay output or
triac output
Surge suppressor
COM
OUT
Relay output or
transistor output
COM
L
OUT
R
COM
R
OUT L
COM
In-floor duct
IN
DC input
L
L
+
Diode
Section 5-3
+
+
1 = I/O cables
2 = Power cables
Conduits