MX-28 Dynamixel Servo (Protocol 2.0)- Hardware Error Status: Overload error


Apologies for multiple or similar post. I have Dynamixel MX-28 actuators with protocol 1.0. They were working fine using Dynamixel Wizard 2.0 - v2.0.1.4 and also using Dynamixel SDK in both Ubuntu 20.04 and Windows 10. When I change the protocol to 2.0 using recovery function of “Dynamixel Wizard 2.0”, I can blink the led. However, when I enable torque and try any operating mode, I get “Overload error” message from the Hardware Error Status control register.

When I change it back to 1.0, I can still use the servos so they are not dead. What causes this problem? According to the documentation, they are compatible with Protocol 2.0. Or am I missing something?

Thanks in advance for your support,

This is a very strange occurrence, normally the overload error happening every time an actuator is torqued on is a sign of full motor failure, but you say it’s only happening when on Protocol 2 firmware?

It’s possible that there is some wear and tear on the motor that only the Protocol 2 firmware is recognizing as an error, but that’s the only simple explanation that I can think of.

If your DYNAMIXELs are operating acceptably on protocol 1 for now it may be best to leave them that way for now, as I think this may require an RMA inspection to find the root cause of the issue.

Hi Jonathon,

Thanks for your reply and advice!

The problem is only happening on Protocol 2. I have same problem with other MX-28 servos. So, I don’t think some sort of wear or tear cause this problem.

I didn’t purchase these servos in person and they may be older than I think. Is there any chance that older version of MX-28 servos are not compatible with Protocol 2?

I haven’t ever encountered anything like that in the past, but I suppose it could be possible?

If Protocol 1 continues to work well I would just keep using that unless you specifically require features from protocol 2, although the MX28 in specific doesn’t gain as many additional features as some other MX series servos.

I would also recommend that once it does become time to upgrade the servos themselves that you transition to the XM430-W350-T, the upgraded, and cheaper, replacement to the MX28

This is really a strange behavior of MX-28.
Would you try updating the DYNAMIXEL Wizard to the latest version ( and try again?
I don’t think older software would cause such problem, but I’d like to exclude uncertain things that can easily be fixed.