Mitsubishi MELSEC-F FX3U Series User Manual

B-15
3 Wiring
3.4 Grounding
A
Common Items
B
FX
3UC
-4AD
C
FX
3U
-4AD-ADP
D
FX
3U
-4DA-ADP
E
FX
3U
-4AD-PT
-ADP
F
FX
3U
-4AD-TC
-ADP
G
PID Instruction (FNC 88)
FX 3U /FX 3UC Series PLC User's Manual - Analog Control Edition
FX3UC-4AD (4-channel Analog Input)
3.3.1 Analog input line
The analog input type, 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 the other motive power lines or inductive lines.
*2. To use the current input, be sure to short circuit the line between the V + terminal and the I
+ terminal ( : channel number).
*3. The SLD and " " terminals are connected to each other inside.
*4. Do not connect any lines to the "•" terminal.
3.4 Grounding
Grounding should be performed as stated below.
• The grounding resistance should be 100Ω 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.
→ For details, refer to the User’s Manual - Hardware Edition of each Series.
• The grounding wire size should be AWG22-20 (0.3 to 0.5 mm
2
).
• The grounding point should be close to the PLC, and all grounding wires should be as short as possible.
250 Ω
6.8k Ω
ch 
200k Ω
FX 3UC -4AD
V  +, I  +, ch  :  represents the channel number.
Terminal
block
I  +
COM 
V  +
*1
I  +
COM 
V  +
250 Ω
6.8k Ω
ch 
200k Ω
*1
If current input is
selected
If voltage input is
selected
*2
•
SLD
SLD
*3
*4
PLC
Another
equipment
PLC
Another
equipment
PLC
Another
equipment
Shared grounding
Good condition
Common grounding
Not allowed
Independent grounding
Best condition

Mitsubishi MELSEC-F FX3U Series Specifications

General

Brand	Mitsubishi
Model	MELSEC-F FX3U Series
Category	Controller
Language	English