Having a system utilizing an Allen Bradley 1394-STJ10-A servo controller that experienced a malfunction in the memory module, I had to replace the controller. The original controller was a firmware version 7.1 series C, while the new one is version 7.1 series A. The main difference between the series is the removal of a fan in the newer version with plugs on the older version. After installation, I consistently encounter a position error on my 1756-M02AE module. There are four axis modules connected to the controller, with only the M02AE module faulting out. The M02AE utilizes an absolute encoder, while the axis modules use a resolver. Two out of the four modules fault immediately upon enabling, while the remaining two fault when attempting to move them. Additionally, the non-faulting modules move slowly without a command speed from the M02AE. The program shows a command speed of around 45 for one and -15 for the other on the HIM once enabled, suggesting possible noise interference. Furthermore, the tolerance for the position error on the M02AE is set to .05 for three of them and .5 for the remaining one. I managed to move the modules by jumpering power to the enable signals and using the jog button on the HIM, indicating that the motors and drives are functioning properly. What other factors should I consider troubleshooting? Additionally, I replaced both M02AE cards in the rack as a precaution and backed up the program on the HIM for transfer to the new controller.
This may pose a challenge as something may have been lost or damaged in the servo controller configuration or encoder. Is your 1394 controlling the servomotor with a motor-mounted resolver? Where is the physically mounted encoder connected to the M02AE? In essence, "M02AE" stands for "Motion, 2 Axis, Analog Output, Encoder Feedback." Typically, the encoder types used are quadrature incremental encoders. For SSI, you would require a 1756-M02AS, or for a magnetostrictive absolute encoder, a HYD02 may be needed. To troubleshoot servo controllers, try using a "Direct Command" on the motion module to set the 0-10V command to a fixed output without closing the position loop.
Do you have the 1394-SJT10-A User Manual PDF from Rockwell Automation? This device is not a GMC or Turbo motion controller, but rather a digital servo drive that accepts Analog 0-10 V position or torque commands. It features numerous programmable parameters that need to be manually loaded from the PLC. Visit the link for more information: https://literature.rockwellautomation.com/idc/groups/literature/documents/um/1394-um000_-en-p.pdf
It sounds like you've done a thorough job addressing most of the hardware aspects, but one factor that may be worth considering is the M02AE module integration with your other equipment. Since only one type of module is faulting, it suggests an issue with either how it interacts with other modules or its programming setup. If you haven't yet, consider checking the communication protocols and ensuring the correct firmware version is installed for application compatibility. Also, the noise interference you mentioned could be a significant issue here. Electromagnetic interference might be triggering false commands or errors. Look into ways of shielding your equipment, moving cables further apart, or introducing noise-filtering technologies if this is the case. Finally, the M02AE module tolerance ranges you mentioned seem quite tight, easing those up a little may prevent unnecessary faulting.
It sounds like you've been quite thorough with your troubleshooting so far. However, with the information given, this could potentially be an issue with how your absolute encoder is interacting with the new controller. Have you run a diagnostic on the encoder module in the PLC? Additionally, while it seems minor, the removal of the fan in the new controller may be causing some thermal issues that are affecting your 1756-M02AE module. Check if the module, or any nearby components, are overheating. Lastly, considering the difference in command speed when enabled, it could be noise interference. Try shielding your cables or moving them away from any potential sources of electrical noise. Don't forget to check for possible ground loops in your system too, they can cause this kind of erratic behavior.
It sounds like you've carried out quite an extensive diagnosis already, so bravo for that. Given that you mentioned the removal of the fan in the newer version, is it possible that this could be causing some overheating issues leading to faulty signals? Also, you might want to check the compatibility of firmware versions between the controller and the 1756-M02AE module. Considering the behavior you’re describing, another possibility could be an issue of electronic noise or crosstalk within the communication lines between the modules and the controller, so hardware shielding or software filters may help. Additionally, you might want to make sure all the plugs and cables are securely fitted. Finally, make sure the parameters/settings specially related to the encoder and resolver in your controller are properly configured. The discrepancy between absolute encoder and resolver could be causing these issues. Even with a backup, there could be nuances in the configuration that are missed during transfer. Hopefully, these potential solutions offer some help. Keep us posted on your progress!
It seems like you've pretty comprehensively checked the hardware side of things. I’d suggest looking into the software configuration next. It's possible that when you switched to the new B series controller, some settings might not have transferred correctly during the firmware update. It's a common issue when upgrading or downgrading. Double check the configuration on the M02AE and see if there are any discrepancies between the old set up and new set up. It might also be worth checking the loop tuning parameters, feedback configuration, and motor parameters. These are small things that could've been overlooked but could definitely cause major problems like you're experiencing.
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Answer: Answer: The position error on the M02AE module could be caused by various factors such as differences in firmware versions between the old and new controllers, encoder type differences, potential noise interference, or incorrect tolerance settings.
Answer: Answer: The faulting of the axis modules could be related to issues with communication, power supply, encoder type compatibility, or noise interference impacting the module's performance.
Answer: Answer: To address the slow movement issue, consider checking for noise interference, verifying proper power supply, ensuring correct encoder settings, and examining communication between the modules and the controller.
Answer: Answer: The tolerance settings on the M02AE module can impact how sensitive the system is to position errors, with different settings affecting the allowable margin of error in positioning. It's important to ensure that the tolerance settings are appropriate for the application and equipment being used.
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