In this walk-thru we’ll look at downloading and uploading to Mitsubishi FX5 and iQ-R controllers.

The same setup was used in the previous Mitsubishi PLC series which includes the preceding (pre-requisite) document with step-by-step on how to connect.

Like any other popular PLC programming software, you can upload and download to the processor as well as other typical tools like compare or verify.  If you know where to look, GX Works3 will also show you ladder differences graphically as well.

The focus of this submission will be downloading, uploading, and some associated steps and tools.

Note: Setting up the connection from GX Works 3 to Mitsubishi PLCs was covered in my previous write-ups here and here.

Step 1) Once connected to the PLC, you will use the Online pulldown menu or the associated quick keys to select what you would initially like to do.

Online Write and Read Option, Image by Paul Hunt

Step 2) Select Read or Write. You will then see the Online Data Operation Window.  Here you can change your choice if you have selected the wrong operation initially.  You can select Write, Read, Verify, or Delete.  Once you have the action selected and everything looks right (usual defaults are typically ok), press Execute.

Data Operation, Image by Paul Hunt

Step 3) Some instances might require that you select options that are not the default. Before pressing “Execute”, you will check (or uncheck) the needed checkboxes that correspond to what you would like to do.  This is where you can select, for instance, Device Memory or Parameters for a Read action so you can make changes, save, and then download without changing registers used for things like recipes or important parameters.

Step 4) If you select Read and press Execute, you will see the Read from PLC dialog appear. Similar to other windows dialog boxes, you can choose to allow it to automatically close if you check the box at the bottom of the window.

Read Dialog Box, Image by Paul Hunt

Step 5) A similar view to the Reading function is created when Writing. You will be able to select the items you want to download in case you only want to download the program logic or maybe just Data Memory or Parameters.

Write Dialog Box, Image by Paul Hunt

Step 6) When you need to verify the offline program with the online version, things get a little different. As shown here, when you select Verify, you can select any part from the program as well as parameters and device memory.

Verify Checked, Image by Paul Hunt

Step 7) If there are differences detected during the reading and compare, you will see a dialog box pop up asking if you wish to continue. Press Yes.

Mismatch Dialog, Image by Paul Hunt

Step 8) While verifying, it will read what was uploaded from the connected controller and then display the Verification Progress dialog window as it proceeds.

Read Verification, Image by Paul Hunt

Step 9) Once completed, you will see any differences highlighted in Pink. If one of the “Program Blocks” is highlighted, you can double click that in the list shown and it will bring up a window with the visible logic compared side by side.  Similar to what is shown in the compare function from Rockwell software for those that are familiar with that.

Mismatch Program, Image by Paul Hunt

As with any software, it is best to take your familiarity with other programs and windows applications to “look around”.  Take a few minutes during projects or set aside some time if you aren’t lucky enough to get some formal training and follow some examples or possibly create some simple projects to learn what you can.  You may be surprised to see how beneficial being familiar is when it comes to creating, copying, or modifying a project in a pinch.

Written by Paul Hunt
Senior Automation Engineer and Freelance Writer

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Paul Hunt


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