Mitsubishi MELSEC-F FX3U Series User Manual

E-13
3 Wiring
3.4 Selection of Platinum Resistance Thermometer Sensor
FX 3U /FX 3UC Series PLC User's Manual - Analog Control Edition
FX 3U -4AD-PT-ADP (4-channel Platinum Resistance Thermometer Data Input)
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)
3.4 Selection of Platinum Resistance Thermometer Sensor
Select the Pt100 3-wire platinum resistance thermometer sensor.
This thermometer will not be affected by voltage drop in the wiring area, and will ensure accurate
measurement.
3.5 Wiring of Platinum Resistance Thermometer Sensor
*1. Separate the cable of the platinum resistance thermometer sensor from the other motive power cables
or areas easily affected by inductive noise (of the commercial power, etc.).
3.6 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 to 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.
100k Ω
ch 
PT-ADP
Class-D grounding
+5V
24+
24-
Twisted shielded
cable
*1
Terminal
block
24V DC
L  +, L  -, I  -, ch  :  represents the channel number.
Pt100
100k Ω
4.7k Ω 4.7k Ω
+5V
100k Ω
ch 
+5V
100k Ω
4.7k Ω 4.7k Ω
Pt100
L  -
I  -
L  +
L  -
I  -
L  +
Shield
Twisted shielded
cable
*1
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