Any simple way of moving 2 nos modulating actuators synchronously with 4-20mA command signals? We have 4-20mA feed back from each of them.

 

Assuming the control signal is 4-20mA, drive both with the same 4-20mA signal in series, or use a 4-20mA splitter which provides an individual 4-20 for each actuator

 

> Assuming the control signal is 4-20mA, drive both with the same 4-20mA signal
> in series, or use a 4-20mA splitter which provides an individual 4-20 for each actuator

Yeah I understand. I just want to do some kind of CROSS COUPLING between actuators so that

(1) failure of one actuator shuts down another. Failure of one actuator can be due to toque limit acting,power loss or loss of feedback

(2) feed backs from the both actuators to be compared and error between them is more than acceptable value, then both actuators to be shut down.

If both actuators do not move synchronously with acceptable error of say +/- 5 mm, the "load" will not move on guide and one actuator may see more frictional forces than other.

I welcome ideas to improve the above thoughts from the learned members of this community!!!

Best Regards

 

-Wire the actuators in series.
-Adjust the actual output towards the desired output at some rate BUT only move the output value as long as the two feedbacks agree within some deadband.

If this were a function block program I'd have the setpoint going to a RAMP block with the output pinned to the RAMP output.

The feedbacks would be have their difference calculated and this value fed into a DEVIATION block with the +/- deviation limits set accordingly. If the HI or LO deviation is active then the output of the RAMP block would be locked/frozen until the deviation cleared.

 

It seems that you'll design a gantry actuator. As you need PLC or motion controller for realize some cross talking algorithms. Using Enable inputs of actuators except control signals 4-20mA maybe suggested also.

 

Thanks for your suggestion.

Can we use 2 axes controller to do the synchronization? Any one experienced in using the above?