Intermittent Fault on Axis 2 of R-10 Robot, Suspected MD132-016 Drive Issue

Description

We are experiencing an intermittent but increasingly frequent fault on Axis 2 of our R-10 robot on production line 3. The system will run normally for several hours, then suddenly trip with an EtherCAT communication loss error specifically related to the drive controlling axes 1 and 2. The teach pendant shows error E-4502. When the fault occurs, Axis 2 becomes unresponsive, while Axis 1, which is controlled by the same NexBot Robotics MD132-016 Multi-Axis Servo Drive, sometimes continues to report its position correctly but cannot be enabled. A full power cycle of the robot controller cabinet, including the 480VAC supply to the drive, is required to clear the fault. We have checked the EtherCAT cabling between the controller and the drive, and the connections are secure. The issue seems to occur more frequently during high-acceleration moves. We suspect a potential failure in the communication board of the drive.

Symptoms

• Robot faults with error E-4502 (EtherCAT Communication Timeout).
• Axis 2 becomes completely unresponsive.
• The drive's 'COMM' status LED flashes red during the fault.
• Problem is intermittent and requires a full system power cycle to resolve temporarily.

Resolution

Support analysis determined the fault was related to an internal failure of the EtherCAT processing components within the servo drive. The customer was guided through diagnostic checks, which included monitoring the EtherCAT bus for dropped packets and examining the drive's internal error log. The logs revealed repeated CRC errors originating from the drive just before communication was lost. Swapping the drive with a known-good spare from another R-10 robot resolved the issue immediately on the production machine, while the faulty drive caused the same error on the test machine. The root cause was confirmed to be a hardware failure within the drive. A replacement unit was dispatched to the customer.

Resolution Steps

1. Connected a laptop to the service port of the EtherCAT bus to monitor network traffic.
2. Observed a high number of malformed packets and CRC errors originating from the suspect MD132-016 drive's MAC address.
3. Guided the customer to safely power down the robot cell using the established Lock-Out/Tag-Out (LOTO) procedure.
4. Instructed the customer to swap the suspect drive (SKU: NXB-SRV-MD132-016) with an identical drive from a non-critical system for testing purposes.
5. After the swap, the production robot (R-10) ran for 48 hours without any recurrence of the E-4502 error.
6. The suspect drive was installed in the test system and produced the same E-4502 fault within 30 minutes of operation.
7. The original drive was confirmed to be faulty. A replacement NXB-SRV-MD132-016 was shipped to the customer under warranty.
8. The customer successfully installed the new drive, restored parameters from backup, and returned the system to full production.