Mitsubishi MELSEC-F FX3U Series User Manual

B-57
8 Troubleshooting
8.1 PLC Version Number Check
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)
8. Troubleshooting
This chapter describes the troubleshooting methods and error codes.
If the A/D conversion data is not input, or if the proper digital value is not input, check the following items:
• Version number of PLC
• Wiring
• Program
• Error status
8.1 PLC Version Number Check
Check the version number of FX3UC-32MT-LT. The version number should be 1.30 or later.
→ For a detailed description of version number check method, refer to Chapter 1.
8.2 Wiring Check
Check the wiring as follows:
1. Power
4AD needs driving power. Verify that the power supply line is properly connected. Also check that the 24 V
indicator lamp of 4AD is on.
2. Analog input line
Use the 2-core twisted shielded cable for the analog input line. In addition, be sure to separate the analog
input line from the other motive power lines or inductive lines.
3. Use of current input mode
To use the current input mode for a channel, be sure to short-circuit the line between the V+ terminal and
the I+ terminal (: channel number) of the channel.
Without short circuiting, it is impossible to obtain the correctly converted digital values.
→ For a detailed description of wiring, refer to Chapter 4.
8.3 Program Check
Check the program as follows:
1. Storage devices
Check whether the device holding digital values contains any values written by other programs.
2. Setting of number of averaging time and digital filter function
Check if the number of averaging time or the digital filter function is set for the same channel. It is not possible
to set both functions for the same channel.

Mitsubishi MELSEC-F FX3U Series Specifications

General

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