320-0056

Access PLC Configuration

Navigate to Setup > General > Machine Parameters > CfgPlcPeriphery and locate the iocProject parameter.

Document the current iocProject value before making changes

Verify IOC Project File

Check if the referenced IOC project file exists in the correct directory path and matches your actual I/O hardware configuration.

Incorrect IOC files can cause unpredictable I/O behavior

Update Configuration

If mismatch found, update the iocProject parameter to reference the correct IOC configuration file or restore from backup.

Always perform a control restart after changing IOC parameters

Check Encoder Connections

Inspect all EnDat and SSI encoder cables for proper connection, damage, or loose connections at both encoder and IOC ends.

Power down the system before checking encoder connections

Verify Encoder Power Supply

Measure encoder supply voltage (typically 5V or 24V) at the IOC terminals and ensure it's within specification tolerance.

Use a digital multimeter with at least 3.5 digit resolution for accurate voltage readings

Test Communication

Access Diagnosis > I/O > Encoder Status to verify individual encoder communication and check for any error flags.

Document encoder serial numbers and firmware versions for future reference

Visual Hardware Inspection

Check all PLC I/O modules for LED status indicators, proper seating in backplane, and any visible damage or overheating signs.

Ensure proper ESD protection when handling PLC modules

Verify Module Configuration

Compare physical module types and positions with the IOC configuration to ensure hardware matches software setup.

Take photos of module arrangements before making any changes

Test Module Functionality

Use TNC diagnostic functions to test individual I/O points and identify specific faulty modules or channels.

Replace suspected modules one at a time to isolate the fault

Check Network Cables

Inspect Ethernet cables between TNC and IOC for damage, proper connection, and verify cable category meets requirements.

Use a cable tester to verify continuity and proper pin-out

Verify IP Configuration

Access Setup > General > Network and verify IP addresses, subnet masks, and gateway settings for TNC and IOC devices.

IP address conflicts can cause intermittent communication issues

Test Network Connectivity

Use TNC network diagnostics to ping IOC devices and check communication latency and packet loss.

Monitor network traffic during initialization to identify timing issues

Check TNC Software Version

Navigate to Help > Info to display current TNC software version and build number.

Document all version numbers for compatibility verification

Verify IOC Firmware

Access IOC diagnostic menus to check firmware versions of all I/O modules and compare with TNC compatibility matrix.

Firmware updates should only be performed by qualified technicians

Update Configuration

If version mismatch found, either update IOC firmware or modify IOC configuration to use compatible feature set.

Always backup current configuration before firmware updates