Checking Installation; Checking Sequence Program; Checking The Communication Settings; Checking Absence/Presence Of Errors - Mitsubishi Electric FX5 User Manual

Checking installation

• Connection status
The communication cannot be operated if the PLC and the communication board/communication adapter are not
connected correctly.
For the connection procedure, refer to the following.
FX5U User's manual (Hardware)
FX5UC User's manual (Hardware)
• Wiring
Verify that all communication equipment is correctly wired. (Page 77 Wiring)

Checking sequence program

A serial port using any other communication (such as RS2 instruction) cannot use an inverter communication instruction.
(Page 212 Combined Use of Serial Communication)

Checking the communication settings

CPU module communication settings
Verify that the protocol type is "Inverter Communication". If the communication settings are not "Inverter Communication",
communication will not function correctly. (Page 95 PLC Communication settings)
After changing communication settings, make sure to turn the PLC power from OFFON, or reset the system.
Checking inverter operation status
1.
When the operation mode of an inverter is not changed to computer link operation mode
• Verify that the inverter is set to the external operation mode.
Verify that no signal is being input to the external terminals STF and STR.
•
• Verify that the correct change operation mode program is being executed.
2.
When an inverter cannot be started even in computer link operation mode
• Verify that the program for starting the inverter is executed correctly.
• Verify that the operation command rights and speed command rights are set correctly.
Verify that the allowable communication time interval is set correctly.
•
3.
When an inverter is stopped by an alarm during operation due to defective communication
Verify that a communication cable is connected correctly between the PLC and the inverter. (Check for poor contact
•
or wire breakage).
• Verify that a sequence program is created so that communication is executed with each inverter within a constant
cycle. Set the communication check time interval to a large value, and check the communication status.
• Verify that the allowable communication time interval is set correctly.
Verify that termination resistors are set correctly.
•

Checking absence/presence of errors

If an inverter communication error occurs, it is processed as a serial communication error. (Page 101)
Serial communication error
■Error flags
The following devices turn ON when an error occurs during serial communication.
FX5 dedicated
CH1 CH2
SM8500 SM8510
4 INVERTER COMMUNICATION
120
4.9 Troubleshooting
FX3 Series
compatible
CH3 CH4 CH1
SM8520 SM8530 SM8063
Name
CH2
SM8438 Serial communication error
Description
Turns ON when an error occurs in serial
communication.