Centroid Community CNC Support Forum

Sd3 drive logic power issue.

I experienced an error 439 depicting x axis encoder data error. Upon looking in the cabinet, there is no logic power indicator illuminated during power up or operation. Two other daisy chained single axis drives have their logic power indicator illuminated. Voltage is equal at all drives.

I assume the x axis is shown as the fault axis due to it being the first on the list being checked, and the logic power failure obviously causes issue with the enc oder signal transmission on the board. Problem remains with all encoder inputs disconnected.

This appears to be an internal failure of the power supply circuitry similar to a large Dell monitor I recently repaired. Are there any common component issues (cap or schottkey perhaps) that can be replaced on an sd3?

I didn't notice any abnormal power at the shop today, however the machine was unattended and it was extremely windy outside, possibly resulting in a power droop.

Previous x axis encoder error was resolved via cleaning the d sub encoder connector with deoxit, however I don't think I have a powerful enough spray to restore internal logic power to the board. Was hoping to cut parts tomorrow and over the weekend as we are a bit backed up. If there is a cap or diode that is known to cause issue I am able to desolder and replace.

Thanks,
John

As an update today, the logic power is now functioning again, and the entire machine functioned normally during initial homing. During a jog move, in the x axis, I noticed an unusually high amount of load showing on the x axis (flashing yellow, and even red).

I performed a drag test and the values are higher then the previously stored data. There is obvious laboring of the x axis servo. I'm not sure if it is mechanical or a result of potentially low output voltage from the drive, etc. If the axis is moved quickly and encoder error will trigger due to the inability of the servo to maintain requested position.

I will check the servo motor windings tomorrow as well as to take a look to see if there are a obvious mechanical issues.

I assume the loss of logic power indication was the product of an overload on the drive.

This whole issue seems odd as it initially occured with no load other then simple table moves (no cutting loads), with no real issues during earlier cutting yesterday, although I suppose quick problems like this are fairly common.

John

Drag test on X axis showing higher drag in red from most recent test

Overall system version / ID info

Pulled the x axis servo last evening and tested resistance and "shorted windings" rotation at both the servo MS connector as well as back at the sd3 drive connections. ~0.9 ohm at the motor and about 1 ohm when including the cable.

Everything will operate as expected until attempting to operate at higher speed which causes peaking on he load meter and subsequent encoder error (presumably from the motor not being able to keep up). I visually inspected the x axis mechanical components and verified lubrication is being delivered to all 4 corners of the table on the x axis.

While the servo was off, I was able to easily rotate the ball screw and translate the table by hand without any unusual resistance (obviously not as fast as a rapid traverse).

Servo nameplate for reference

Please send us a report of the system to tech@ajaxcnc.com . To generate a report, from the main menu, press F7 Utilities, then F7 Report. We just need the report.zip created. The report will include your settings, parameters, and faults you are experiencing. That will allow our tech support to have the full system picture for troubleshooting.

Thanks for the response. I worked with Centroid tech folks and ended up performing all sorts of tests. Problem ended up being a faulty wire inside the backshell of the servo encoder cable fo the x axis.

While I was in there swapping motors, cables, etc, I took care of lots of needed maintanence. Machine works great now aside from an incomplete system test error at startup that I am unable to remedy due to machine interference (may need to see where to modify the system file to move the table to full +y before traversing the x and z (z will clear barely if x axis table and spindle drive dogs are removed)to prevent contact with a trt-32.

Tech support from Ajax / centroid is better than anything I have ever experienced, especially for a DIY customer.

John

Offending backshell /wire

"Tech support from Ajax / centroid is better than anything I have ever experienced, especially for a DIY customer. "

John, Thanks for the stoke, i'll pass it on to the Centroid Tech Support crew, Mario, Scott and Liviu. these guys are dedicated and knowledgeable. Based in the USA supporting a made in USA product. Thanks for being a Centroid customer we continually strive to innovate and produce CNC technology that performs at a Industrial Quality Level while still being within reach of the Do-it-Yourself CNC control builder. -Keith