Analog Input Line; Grounding - Mitsubishi Electric FX3G User Manual

FX /FX /FX /FX /FX
3S 3G 3GC 3U
FX -4AD-ADP (4-channel Analog Input)
3U
3.4

Analog Input Line

For analog input, "voltage input" or "current input" can be selected for each channel.
*1. Use the 2-core shielded twisted pair cable for the analog input lines, and separate the analog input
lines from other power lines or inductive lines.
*2. If "current input" is selected, be sure to short the line between the V+ terminal and the I+ terminal.
(: Channel number).
*3. For FX
3S
available.
3.5

Grounding

Grounding should be performed as stated below.
• The grounding resistance should be 100 Ω or less.
• Independent grounding should be performed for best results.
When independent grounding is not performed, perform "shared grounding" as shown in the following
figure.
PLC
equipment
Independent grounding
Best condition
• The grounding wire size should be AWG22 to 20 (0.3 to 0.5 mm
• The grounding point should be close to the PLC, and all grounding wires should be as short as possible.
C-16
PLC User's Manual - Analog Control Edition
3UC
If current input is selected:
*1
If voltage input is selected:
*1
Connection of external
power supply line
24V DC *3
Class-D
grounding
V+, I+, ch : represents the channel number.
/FX /FX Series PLC (AC power type), the 24 V DC service power supply is also
3G 3U
→ For details, refer to the User's Manual - Hardware Edition of each PLC Series.
Other Other
PLC
equipment
Shared grounding
Good condition
4AD-ADP
Terminal
block
147kΩ
V+
250Ω
*2
I+
47kΩ
COM
147kΩ
V+
250Ω
I+
47kΩ
COM
24+
24-
Other
PLC
equipment
Common grounding
Not allowed
3.4 Analog Input Line
ch
ch
+15V
2
).
3 Wiring