Omron ZEN Operation Manual page 66

Wiring
NPN
output
NPN
output
3. Use only PNP sensors for pre-V1 CPU Units. NPN sensors can-
not be connected directly. To connect an NPN sensor, connect it
through a relay or connect external resistance, as shown below.
Be sure to allow for the reverse logic that will result from this type
of connection
• Connecting to I0 to I3
External
resistance
20.4 VDC
1 kΩ
min.
I0 to I3
a) When an NPN sensor is connected, use an external resis-
tance R of at least 1 kΩ and 2 W.
b) Use a power supply voltage of at least 20.4 VDC for the sen-
sor.
• Connecting to I4/I5
External
resistance
20.4 VDC
min.
I4, I5
c) When an NPN sensor is connected, use an external resis-
tance R of at least 82 kΩ and 1/8 W.
d) Use a power supply voltage of at least 20.4 VDC for the sen-
sor.
e) Do not input a negative (–) signal to the analog inputs (I4, I5).
The internal elements may be damaged if a negative signal
is input.
4.1 kΩ
680 Ω
150 kΩ
2.4 kΩ
Section 2-2
Internal
circuit
Internal
circuit
43