23A-0019

Identify affected device

Note the device name or number shown in the %2 parameter of the alarm. Cross-reference this with the machine's network topology diagram or MOD > System Configuration > Device List to locate the physical device.

The %2 parameter typically shows the device name as configured in the PLC program (e.g., 'Spindle_Drive', 'Tool_Magazine', 'MPG_Panel').

Inspect physical connections

Check all cable connections between the TNC control's PLC module (typically X115 for ProfiNet) through any network switches to the affected device. Verify M12 and RJ45 connectors are fully seated and locking mechanisms engaged.

Power down peripheral devices before disconnecting/reconnecting network cables to prevent backplane damage.

Verify cable continuity

Use a network cable tester or multimeter to verify continuity on all twisted pairs. For ProfiNet, confirm proper shielding continuity. Check for cable damage especially near cable carriers or moving machine components.

Heidenhain recommends Cat5e minimum for ProfiNet; Cat6 or industrial M12 X-coded cables for machine tool environments with high EMI.

Check LED indicators

Observe the LED status on the TNC PLC module X115/X116 connector area and on the affected device's communication port. Green typically indicates link OK, flickering shows data activity, red/amber indicates fault. No LED activity confirms physical layer failure.

On TNC 640 controls, the PLC module LEDs are visible through the front panel access window without opening the cabinet.

Access network configuration

Press MOD function, navigate to System Configuration > Network Configuration. Review the configured devices list and note the IP address and device name of the affected device (%2 parameter).

On iTNC 530, access via MOD > General > Network Settings. Path varies slightly by TNC model and software version.

Verify IP addressing scheme

Confirm the affected device has a unique IP address within the machine network subnet (typically 192.168.x.x range). Check that subnet mask matches across all devices (commonly 255.255.255.0). Verify no IP conflicts exist with other devices.

Heidenhain typically uses 192.168.214.x subnet for control networks. Document all device IPs before making changes.

Check device station address

For Profibus devices, verify the physical rotary switch or DIP switch station address on the device matches the address configured in MOD > PLC > Configuration > Profibus Slaves. Addresses must be unique on the Profibus segment.

Always power down Profibus segment before changing station addresses to prevent network corruption.

Validate PLC device configuration

Access MOD > PLC > Configuration and verify the device type, communication parameters (baud rate, cycle time), and GSD file match the physical hardware. Incorrect device configuration files cause protocol mismatches.

After PLC configuration changes, a full control reboot is required. Use MOD > Service > Reboot Control, not just PLC restart.

Test network connectivity

If ProfiNet/Ethernet device, use the control's built-in ping utility: MOD > System Configuration > Network Tools > Ping Test. Enter the device IP address to verify Layer 3 connectivity before troubleshooting protocol layers.

Successful ping but continued 23A-0019 alarm indicates application layer (protocol configuration) issue rather than physical network problem.

Verify device power indicators

Check the affected peripheral device for power LED indicators. Most devices have separate LEDs for power (steady green) and communication (flickering green/yellow). No power LED indicates supply failure rather than communication fault.

Measure voltage with cabinet power on. Use appropriate PPE and lockout procedures per machine safety requirements.