Fuji Electric MICREX-SX series SPF - Input Circuit Configuration and External Connection

3-6
Section 3 Specications
(2) Input circuit conguration and external connection
The 24V DC digital input circuits are available for high, medium and low speed. They all have the similar circuit structures but
with different response speeds. When making the connection of external digital input devices, the one ends of all input devices
(e.g. buttons and switches) are connected together and called the external common wire, while the other ends of input circuits
are connected to the input terminals X0, X1, X2, etc., of SPF. Then nish it by connecting the external common wiring and
internal common terminal S/S to the 24VDC power. When connecting the internal common terminal S/S to 24V+ (positive) and
the external common wire to 24V- (negative), then the circuit serves as a sink input. On the contrary, while exchange the wiring
of the above internal and external common will serve as a source input. The above wiring schemes can illustrated below:
• Wiring of source input
• Wiring of sink input
R2
R2
R2
R2
SPF
24V DC
X0
X1
X3
S/S
NPN
sensor
-
+24V
24V DC
X1 X2X0
R1
R1
R1
X3
R1
External common line
Input device
(Not available when using
an expansion unit without
power supply.)
Internal
common
terminal
External
power
supply
X2
X0
24V DC
X3
+24V
-
S/S
X0
24V DC
X3
X1 X2
R1
R1
R2
R2
R2
R1
R2
R1
SPF
X1 X2
PNP
sensor
External common line
Input circuit
(Not available when using
an expansion unit without
power supply.)
External
power
supply
Internal
common
terminal