2A0-0009

Inspect Physical Connections

Power down the TNC and check all Ethernet cable connections at the TNC X116/X26 (depending on model) interface and at the network switch/PC. Look for bent pins, loose RJ45 clips, or physical damage to cables.

Always power down the TNC before disconnecting/reconnecting communication cables to prevent damage to interface circuits.

Test Cable Continuity

Use a cable tester to verify all 8 wires have proper continuity and that the cable meets CAT5e or better standards. Replace any suspect cables with known-good shielded Ethernet cables rated for industrial environments.

Heidenhain recommends shielded CAT5e or CAT6 cables with maximum length of 100 meters for LSV2 Ethernet communication. Keep cables away from high-voltage power cables and VFDs.

Verify Link Status on TNC

Power up TNC and access MOD > 'System Information' > 'Network Status'. Verify the Ethernet interface shows 'Link Active' and check for packet errors or collision counters that indicate physical layer problems.

High packet error rates (>0.1%) indicate cable quality issues even if link is active. Monitor this during active LSV2 communication.

Verify LSV2 Protocol Settings

Access MOD function > 'System Parameters' > 'Communication Settings' > 'LSV2 Configuration'. Note the configured LSV2 port (typically 19000) and protocol version. Ensure these match your client application (TNCremo, TNCserver) settings exactly.

TNC 640 and iTNC 530 (34059x-06 and later) support LSV2 protocol version 2. Older software may only support version 1, causing incompatibility.

Check Client Software Configuration

In TNCremo or TNCserver, verify connection settings match TNC configuration: IP address, LSV2 port number, timeout values (typically 5000ms), and protocol version. Test connection using the built-in connection test function.

Increase timeout values to 10000ms or higher when connecting over slower networks or VPN connections to prevent false transmission errors.

Reset LSV2 Configuration to Defaults

If configuration is uncertain, reset LSV2 parameters: MOD > 'System Parameters' > 'Communication Settings' > select 'Reset LSV2 to Default'. This sets standard values (Port 19000, Protocol v2). Reconfigure client software to match.

Resetting communication parameters may affect other network services. Document current settings before resetting.

Verify Network Port Accessibility

From the client PC, use command prompt to test: 'telnet [TNC_IP_Address] 19000'. If connection fails, LSV2 port is blocked. Check Windows Firewall, antivirus software, and network firewall rules to allow TCP port 19000 bidirectionally.

Use 'Test-NetConnection -ComputerName [TNC_IP] -Port 19000' in PowerShell on Windows 10/11 for more detailed connection diagnostics including routing information.

Check Network Switch Configuration

Verify network switch settings if TNC is on industrial network. Ensure port is configured for full-duplex operation, spanning tree is disabled or properly configured, and VLAN settings allow communication between TNC and client. Test with direct PC-to-TNC connection to isolate switch issues.

Managed switches with IGMP snooping or port mirroring enabled can interfere with LSV2. Temporarily connect TNC directly to PC to rule out switch-related issues.