Hello, I have a FX3U PLC that I received from an OEM, and I am attempting to extract the original program using GX Works 2. However, I encountered an error during the upload process indicating that the program may have been written in structured text or FB. This could result in the uploaded program being different from the original one. I reached out to Mitsubishi support, and they informed me that in order to upload a program with structured text and FB, I would need the original code from the OEM. The support team also mentioned that I can download the uploaded program in ladder logic form without making any modifications, and it should function the same as a backup. Questions: 1. Is there a method to upload the program in its original format? 2. If the program was converted to ladder logic during the upload process, can I safely make changes to it and download those modifications? I am looking to edit the current PLC program. I have included the uploaded file for reference. Thank you!
It is highly probable that you won't be able to upload in the original format because the symbolic data was not downloaded to the PLC. Additionally, there is no attachment available.
Check out the program that has been uploaded.
The other commenters are correct - without the symbolic table downloaded by the original programmer, it cannot be reconstructed. It's important to determine if the file is from GXWorks or the older GXIEC, as errors (highlighted in yellow) can occur when opening it. These errors indicate that the file may not function normally and could prevent it from being downloaded. This issue is commonly seen when using GXIEC, which can generate code that may not initially appear compatible but still works. To restore the structured project, the best option is to contact the original supplier to obtain the file or manually reconstruct it, although this process is challenging and prone to errors.
I successfully resolved the highlighted issue by making changes to the M8000 in GXWorks2, enabling a rung before reverting it back and re-compiling the code. GXWorks2 operates by utilizing jumps to pointers, allowing for code to be placed outside of the main scan in structured blocks or function blocks. This approach involves conditions like MAIN.A xxxx and CJ P2048, with the use of conditional and unconditional jumps to different blocks within the code. It essentially functions as one continuous code, navigating through various blocks and returning to the main ladder as needed. It is essential to upload PLC parameters and Device memory to ensure consistency across files and preserve fixed data in case of PLC replacement. This should be done when the machine is not in operation.
Thank you, Parky, for responding. I encountered an error when trying to upload using the Select All option as it indicated that my device name was empty. I managed to successfully upload the program by selecting the Parameter+Program option instead. If I need to replace the PLC in the future, can I download and use the program you provided with the same functionality? Editing this program will be challenging without a tag/comment list since the manufacturer has left the comment memory as "0" (no comments).
It sounds like you've run into a common issue with proprietary code on PLCs. Unfortunately, if the original program was written in structured text or function blocks, and you don’t have access to that specific code, your best bet is to work with the ladder logic you’ve uploaded. While you can edit it, just be mindful that changes could affect how the program operates, especially if the original logic was complex. It might help to carefully document any modifications you make, and consider testing those changes in a safe environment before deploying them to the actual system. If you ever get the chance to obtain the original code from the OEM, it would definitely simplify the process!
It sounds like you're facing quite a challenge! Unfortunately, if the original program was written in structured text or function block and you don't have access to that specific code, the upload will indeed limit you to working with just the ladder logic. As for making changes, you can modify the downloaded ladder logic, but be cautious—without the original structured text or FB, some functionalities may not translate perfectly, so extensive changes could introduce issues. If it's possible, I’d recommend reaching out to the OEM again to see if they can provide the original program; that would save you a lot of headaches!
It sounds like you're in a bit of a tricky situation with your FX3U PLC. Unfortunately, as you've learned from Mitsubishi support, without the original code, there's no straightforward way to upload the program in its original structured text or function block format. Regarding your question about making changes to the ladder logic version after uploading, you should be able to modify it without major issues, but just be cautious. Since the upload process can introduce discrepancies in the logic, it's a good idea to thoroughly test any changes you make before deploying them to ensure that everything operates as expected. If you have the resources, creating a backup before editing is always a smart move. Good luck with your project!
It sounds like you're in a bit of a tough spot with the FX3U PLC. Unfortunately, without the original structured text or FB code, you're pretty much limited to working with the ladder logic version you can upload. You might consider reaching out to the OEM again to see if they can provide the source code, which would save you a lot of hassle. As for making changes to the ladder logic, you can definitely edit and download those modifications, but be cautious—since the ladder logic may not capture all the nuances of the original program, testing thoroughly after any changes will be crucial to ensure everything runs smoothly. Good luck!
✅ Work Order Management
✅ Asset Tracking
✅ Preventive Maintenance
✅ Inspection Report
We have received your information. We will share Schedule Demo details on your Mail Id.
Answer: Answer: According to Mitsubishi support, to upload a program with structured text and function blocks in its original format, you would need the original code from the OEM. Otherwise, the uploaded program may be converted to ladder logic form.
Answer: Answer: Mitsubishi support indicated that you can download the uploaded program in ladder logic form without making any modifications, and it should function the same as a backup. However, it is recommended to consult with the OEM or Mitsubishi support before making changes to the program to ensure compatibility and proper functioning.
Join hundreds of satisfied customers who have transformed their maintenance processes.
Sign up today and start optimizing your workflow.