235-0099

Access Machine Parameters

Press MOD key, select 'Machine Parameters' and navigate to MP7300-MP7399 (HSCI configuration parameters).

Always backup current parameters before making changes using the parameter export function.

Check Hardware Configuration

Review MP7310 (HSCI device configuration) and MP7320 series parameters to verify configured devices match actual hardware installation.

Incorrect parameter changes can disable machine functionality.

Verify Option Switches

Check software option switches in MOD > Software Options to ensure hardware expansion options match the physical configuration.

Document all option switch settings before modifications for easy rollback.

Restart Control

Perform a complete power cycle of the TNC control to reinitialize HSCI communication with corrected parameters.

Identify Missing Device

Note the device type and name shown in the alarm message (%1 parameter) to identify which specific HSCI component is missing.

The alarm message shows the exact configured name from the project file.

Inspect HSCI Connections

Physically check all HSCI cable connections, particularly the device mentioned in the alarm, for loose connections or damaged cables.

Power down the control before checking connections to prevent damage.

Verify Cable Integrity

Test HSCI cable continuity and check for proper termination resistors at the end of the HSCI chain.

HSCI cables are sensitive to electromagnetic interference - check routing away from power cables.

Test Device Power Supply

Verify that the missing device has proper 24V DC power supply and check LED status indicators on the device.

Check Device Address Settings

Verify the physical address switches or jumpers on the HSCI device match the configured address in MP7310 series parameters.

HSCI addresses must be unique and sequential starting from address 1.

Scan HSCI Bus

Use TNC diagnostic function MOD > Diagnosis > HSCI to scan for all devices present on the bus and compare with configuration.

Bus scanning should only be performed by qualified personnel.

Resolve Address Conflicts

If duplicate addresses are found, reconfigure device addresses ensuring each HSCI device has a unique sequential address.

Document the address assignment scheme for future reference and troubleshooting.

Locate Bus Termination

Identify the last device in the HSCI chain and verify proper termination resistor installation (typically 120 ohm).

Only the last device in the chain should have termination enabled.

Measure Termination Resistance

With power off, measure resistance across HSCI bus terminals at the end of the chain to verify proper termination.

Disconnect power before resistance measurements to avoid equipment damage.

Check Intermediate Devices

Ensure all intermediate HSCI devices have termination disabled and are properly configured as pass-through devices.

Isolate Suspected Device

Temporarily remove the suspected faulty device from the HSCI chain and bridge the connection to test if other devices respond.

Only qualified technicians should modify HSCI connections with proper ESD precautions.

Test with Known Good Device

If available, substitute the suspected device with a known working unit of the same type to verify device failure.

Keep spare HSCI devices for quick troubleshooting and minimal downtime.

Check TNC HSCI Interface

If all devices fail to respond, suspect the TNC's HSCI interface card and contact Heidenhain service for interface diagnostics.