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Block Transfer Error "The Requested Length is Different than Response Length"
Good day,
I just completed an upgrade from PLC5 to ControlLogix. Everything on the RIO tree pulled up correctly (no yellow triangles with exclamation marks). I then start looking over the message blocks for the BTR/BTW when I notice the following error "The Requested Length is Different than Response Length.
Some background:
1756-L73 controller using a 1756-DHRIO module.
The Block Transfer Read/Write connects to a Prosoft 5601-RIO-MCM gateway, which then connects to a Robicon 454GT drive. This drive was before my time and understanding the full nature of how the registers work is a learning progress.
Now this drive worked fine before the upgrade, which rules out the 5601 gateway and the drive itself.
The message block BTR/BTW reads and writes 64 words. When I look in the configuration file for the 5601, it was setup for only 60 words. I changed the message block BTR/BTW to 60 words. Same error.
I have also verified the R/G/S numbers. Besides that, there really isn't too much for options in that message block, which also makes it very frustrating.
Also to note is I can start/stop and send a reference speed to the drive from the controller, which means there is some communication happening. What I don't see is feedback, errors, running, etc, which is kind of important for control.
Any ways, let me know what you guys figure or things to try. Other message block BTR/BTWs are working fine for the other drives (different models of course, AB 1336), just this one is puzzling.
Thanks for your time!
Good day,
I just completed an upgrade from PLC5 to ControlLogix. Everything on the RIO tree pulled up correctly (no yellow triangles with exclamation marks). I then start looking over the message blocks for the BTR/BTW when I notice the following error "The Requested Length is Different than Response Length.
Some background:
1756-L73 controller using a 1756-DHRIO module.
The Block Transfer Read/Write connects to a Prosoft 5601-RIO-MCM gateway, which then connects to a Robicon 454GT drive. This drive was before my time and understanding the full nature of how the registers work is a learning progress.
Now this drive worked fine before the upgrade, which rules out the 5601 gateway and the drive itself.
The message block BTR/BTW reads and writes 64 words. When I look in the configuration file for the 5601, it was setup for only 60 words. I changed the message block BTR/BTW to 60 words. Same error.
I have also verified the R/G/S numbers. Besides that, there really isn't too much for options in that message block, which also makes it very frustrating.
Also to note is I can start/stop and send a reference speed to the drive from the controller, which means there is some communication happening. What I don't see is feedback, errors, running, etc, which is kind of important for control.
Any ways, let me know what you guys figure or things to try. Other message block BTR/BTWs are working fine for the other drives (different models of course, AB 1336), just this one is puzzling.
Thanks for your time!