Mitsubishi FX A & Q Series PLC Troubleshooting

Course overview
Manufacturers are increasingly facing greater pressures to reduce costs and maintain efficiency whilst also maximising output. These problems are further challenged when it comes to arranging shift patterns to release essential production line staff for training.

This problem can be eased, as we now offer you two and three day courses rather than our more traditional five day courses on Mitsubishi FX Q and A Series PLCs. This two day course enables you to maintain your efficiency levels with the minimum of disruption, whilst also providing focused learning.

The troubleshooting course targets maintenance personnel who have attended the three day First Line Maintenance course or who have a reasonable working knowledge of Mitsubishi and who need to be able to use the full diagnostic toolkit to effectively troubleshoot Mitsubishi hardware problems and machine or process faults. The course is entirely practical and consists of troubleshooting a range of fault scenarios to establish a logical approach to fault-finding and to reinforce the use of standard tools and test procedures.


Target Group
All engineering personnel involved with the maintenance, servicing troubleshooting of automated systems controlled by Mitsubishi FX Q and A Series PLC Systems.


Syllabus

Logical Approach to Fault-finding

• Understand what should be happening
• Understand what is/is not happening
• Understand the reasons why most faults will not be PLC hardware or software & are much  more likely to be due to field device failures or wiring problems
• Define the symptoms & consider possible causes
• Perform appropriate checks to localise the problem

Troubleshooting Mitsubishi FX, Q & A Series hardware problems

• Know the first level checks to begin to quickly distinguish between PLC & field faults
• Know typical fault symptoms for common PLC hardware (module) failures
• Be able to recognise & interpret the meaning of external system diagnostic LEDs
• Be able to correctly interpret the status of I/O LEDs & relate these to the operation of field  devices to distinguish between I/O module faults & wiring or field faults
• Know how & where to use a meter to check & confirm I/O module power supplies & for  correct operation of digital & analog I/O circuits
• Know quick methods to identify a failed I/O module
• Know the symptoms of using a faulty comms cab

Mitsubishi PLC system Resets & Re-starts

• Understand the effect on the operation of the PLC (program & memory) of stopping & re- starting (Stop-Run) or cycling power
• Understand the implications of Retentive/Non-Retentive memory
• Understand how & when to use “Clear PLC memory”, Resets & Latch Clears &  understand the effect of these on system operation
  

Troubleshooting “simple problems” through interpreting Mitsubishi program code

• Review the different display modes that are available
• Know how to use the Search & Cross Reference tools in a program to trace I/O status
• Know the conditions under which on-screen status is displayed incorrectly

Diagnostic tools in GX Developer

• Know how to generate on-screen Cross Reference data
• Know how to Compare a program in the PLC with a program on disk & be able to interpret  the report
• Know how to set up & use the Device/Batch Monitors to monitor multiple I/O points & data  registers
• Know how to use the Device Test with Mitsubishi to set/reset a point or to step-on a  sequence & understand the dangers
• Know how to use the PLC Diagnostic facility & how to interpret the information

Tips & Tricks when Troubleshooting with Mitsubishi

• Know the easy methods to be able to move around larger programs more effectively
• Simple program tools to time or count events, to prove status & trap intermittent faults

Further Mitsubishi troubleshooting practicals

• Troubleshooting “more complex” problems
• Troubleshooting data handling problems
• Troubleshooting problems with analogs
• Troubleshooting problems which include Indirect Addressing