Omron B7A Manual page 103

B7A
Peripheral Circuits of Modular Model
Input Interface Circuit
The modular model has a minimum ON discrimination voltage of 2.2
V and a maximum OFF discrimination voltage of 0.8 V, which are
suitable for TTL circuits. If sensors are used for input, the following
input circuits are required.
Two-wire DC Sensor Input
If a two-wire DC sensor is used for input, current limit resistor R
leakage current diverter R are required as shown in the diagram
2
below. The following table lists R
Two-wire DC Proximity Sensor (with a current leakage of 0.8 mA
maximum, a residual voltage of 3 V maximum, and a minimum con-
trol output current of 3 mA).
Input Interface (E2E-XD-N)
Supply voltage
1,800 Ω
R
1
820 Ω
R
2
Two-wire DC
proximity sensor
R
1
R
2
Noise Protection Circuits
If there is a possibility of noise interference from the power supply, input, and/or output lines, add the following noise protection circuits.
Power supply noise protection circuit
+
R
12 to
+
24 VDC
C
–
B7A
R: 10 to 20 Ω (1/8 W min.)
C: 33 µF min with a dielectric strength of 50 V min C: 33 µF min. with a dielectric strength of 50 V min.
1
and R values for the E2E-XD-N
1 2
12 V 24 V
5,600 Ω
820 Ω
+ Interior of B7A
IN
–
Input noise protection circuit
Input device
V
C: 0.1 µF min.
R: Photocoupler input current limit resistor
Input device
ZD: V = 36 V
ZD
(with a power consumption of 1 W min.)
Input with B7A and Common Power Supply
(12 to 24 VDC) (10-point Modular Model only)
The 10-point modular model has an input voltage range of 0 to 5
VDC. If a common power supply is connected, current limit resistor
R is required as shown in the diagram below. Use the following for-
3
mula to calculate the value of R
Supply voltage V
and
R =
3
Input current (2 x 10
Vs (12 to 24 VDC)
Note: The 16-point module's input voltage range is 0 V to the
power supply voltage. Therefore no current limit resis-
tor is required.
V
1N
R
+
C
IN
Photocoupler
–
B7A
IN
ZD
–
B7A
.
3
(V) – 1.4 (V)
S
– 2,200 (Ω)
–3
(A))
Interior of B7A
+
IN 2.2 kΩ
R
3
–
Output noise protection circuit
Photocoupler
R
+ Load
ZD
OUT
–
R: Photocoupler input current limit resistor
ZD: V = 36 V (with a power consumption
ZD
of 1 W min.)
B7A
+
Load
OUT
ZD
–
ZD: V = 36 V
ZD
(with a power consumption
B7A
of 1 W min.)
B7A
V
101