Mitsubishi Electronics MELSEC-F Manuel D’Utilisation

3 Wiring

FX

3G

/FX

3U

/FX

3UC

 PLC User's Manual - Analog Control Edition

FX

3U

-4AD-PT-ADP (4-channel Platinum Resistance Thermometer Data Input)

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.

*1.

Separate the cable of the platinum resistance thermometer sensor from the other power cables or 
areas easily affected by inductive noise (of the commercial power, etc.).

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.

→ For details, refer to the User’s Manual - Hardware Edition of the PLC 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

Other

equipment

PLC

Other

equipment

PLC

Other

equipment

Shared grounding

Good condition

Common grounding

Not allowed

Independent grounding

Best condition