FATEK FBs-4DA - 6.3 24 VDC Single-End Input Circuit and Wiring for SINK;SRCE input

H6-3
6.3 24VDC Single-End Input Circuit and Wiring for SINK/SRCE input
The 24VDC single-end digital input circuits of FBS-PLC are available for high, medium and low speed. They all have
the similar circuit structures but with different response speeds. To save input terminals, the circuit of single-end input is
implemented by connecting one end of all input points (photo coupler) inside the PLC to the same internal common
point labeled as S/S. The other end of each input circuit is connected to corresponding terminals such as X0, X1, X2,
etc. The S/S common terminal and N single-end inputs comprise of N digital inputs (i.e., only N+1 terminals are used
for N terminals). Therefore, we call this type of input structure the single-end input. The user also needs to do the same
thing when making the connection of external digital input devices. Namely, the one end of all input devices (e.g.,
buttons, 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 PLC. Then finish it by connecting the external common wiring
and internal common terminal S/S to the positive/negative terminals of the 24VDC power. When connect the internal
common terminal S/S to 24V+(positive) and the external common wire to 24V－ (negative), then the circuit serve as
SINK input. On the contrary, while exchange the wiring of the above internal and external common will serve as a
SRCE input. The above wiring schemes can illustrated below:
z Wiring of single-end common SINK input (internal common terminal S/S → 24V+, external common
wiring → 24V－)
R2
R2
R2
R2
FBS
|
PLC
24VDC
(擴充模組無)
X0 X1 X2
X3
S/S
NPN
Sensor
24V-
24V+
外部
電源
24VDC
外部共線
X1 X2
X0
R1
內部共點
端子
R1
R1
X3
R1
輸入元件
z Wiring of single-end common SRCE input(internal common terminal S/S → 24V－, external common
wiring →24V+)
FBS
|
PLC
X0
24VDC
(擴充模組無)
X1 X2
X3
PNP
Sensor
外部
電源
24V+
24V-
內部共點
端子
S/S
X0
24VDC
外部共線
X3
X1 X2
輸入元件
R1
R1
R2
R2
R2
R1
R2
R1
External Common Wirin
g
External Common Wiring
External
Power
(not available in
expansion modules)
Input Circuit
In
p
ut devices
(not available in
expansion modules)
Internal
Common
Te rm in al
External
Power
Internal
Common
Te rm in al
Low speed
R1:5.6K
R2:1KΩ
Middle speed
R1:3.3KΩ
R2:1.2KΩ