Omron CPM2C-S100C Operation Manual page 95

Wiring and Connections
Leakage Current
Inductive Loads
1,2,3...
A leakage current can cause false inputs when using 2-wire sensors (proxim-
ity switches or photoelectric switches) or limit switches with LEDs. False
inputs won't occur if the leakage current is less than 1.0 mA. If the leakage
current exceeds these values, insert a bleeder resistor in the circuit to reduce
the input impedance, as shown in the following diagram.
2-wire sensor, etc.
I: Device's leakage current (mA)
R: Bleeder resistance (kΩ)
W: Bleeder resistor's power rating (W)
L
C
R =
I × L
The equations above were derived from the following equations:
Input voltage (24)
R ×
Input current (I
I ×
Input voltage (24)
R +
Input current (I
Input voltage (24)
W ≥
Refer to 2-1-3 I/O Specifications
The input impedance, input current, and OFF voltage may vary depending on the
input being used. (IN00000 through IN00002 have different values.)
When connecting an inductive load to an input, connect a diode in parallel
with the load. The diode should satisfy the following requirements:
1. Peak reverse-breakdown voltage must be at least 3 times the load voltage.
2. Average rectified current must be 1 A.
Input power
supply
R
CPM2C-S
Bleeder
resistor
L : CPM2C-S' input impedance (kΩ)
C
I : CPM2C-S' input current (mA)
C
E : CPM2C-S' OFF voltage (V) = 5.0 V
C
× 5.0
2.3
kΩ max. W =
−5.0
R
C
)
C
≤
OFF voltage (E
)
C
× Input voltage × tolerance (4)
R
for details on the values L
Diode
Section 3-4
W min.
: 5.0)
C
, I , and E .
C C C
IN
CPM2C-S
COM
73