Troubleshooting; Plc Version Number Check; Wiring Check; Program Check - Mitsubishi Electric FX3G User Manual

FX /FX /FX /FX /FX
3S 3G 3GC 3U 3UC
FX -4AD/FX -4AD (4-channel Analog Input)
3U 3UC
8.

Troubleshooting

This chapter describes 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:
• PLC version number
• Wiring
• Program
• Error status
8.1

PLC Version Number Check

Verify that the PLC being used is of the following version or later.
FX -4AD
3U
Compatible PLC
FX Series PLC
3G
FX Series PLC
3GC
FX Series PLC
3U
FX Series PLC
3UC
FX -4AD
3UC
Compatible PLC
FX Series PLC
3GC
FX Series PLC
3UC
8.2

Wiring Check

Check the wiring as follows:
1. Power
The 4AD needs driving power. Verify that the power supply line is properly connected. Also check that the 24
V indicator lamp of the 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 any other 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 of the channel.
Without short circuiting the terminals, it is impossible to obtain the correctly converted digital values.
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 averaging time and digital filter function
Check if the 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.
PLC User's Manual - Analog Control Edition
Version number
Ver. 1.00 or later
Ver. 1.40 or later
Ver. 2.20 or later
Ver. 1.30 or later
Version number
Ver. 1.40 or later
Ver. 1.30 or later
→ For a detailed description of version check method,
refer to A. Common Items Subsection 5.1.2.
→ For a detailed description of wiring, refer to Chapter 4.

8 Troubleshooting

8.1 PLC Version Number Check

B-61
A
B
C
D
E
F
G
H
I
J