2110

Check Battery Status

Navigate to HMI > Diagnostics > Hardware > NCU and check battery voltage display. Normal voltage should be 3.4-3.8V.

Battery voltage below 3.2V will trigger memory corruption even if system appears functional.

Replace NCU Battery

Power down system completely, replace lithium battery (typically CR2032 or equivalent) on NCU module following proper ESD procedures.

Always power down NCU before battery replacement to prevent data corruption.

Restore Machine Data

After battery replacement, restore machine data from backup archive via HMI > Commissioning > Data Backup/Restore or load INI files from CF card.

Always verify MD11210 (memory test enable) is set to 1 after data restoration.

Perform Memory Test

Execute complete SRAM test via HMI > Diagnostics > Memory Test or set MD11200 to force extended memory check on next startup.

Analyze Memory Test Results

Access HMI > Diagnostics > NCK > Memory and review detailed memory test log to identify specific failing memory addresses or patterns.

Consistent failures at same memory addresses indicate hardware defect rather than data corruption.

Check NCU Module LEDs

Examine NCU front panel LEDs for error patterns. Red ERROR LED with specific blink codes indicates hardware faults per SINUMERIK diagnostic manual.

Do not attempt to repair NCU modules - they contain sensitive components requiring factory-level service.

Verify NCU Part Number

Record NCU module part number and firmware version from HMI > Commissioning > HW Config > NCU for replacement ordering.

Newer NCU versions may require firmware compatibility checks with existing drive modules.

Prepare for NCU Replacement

Create complete system backup including machine data, PLC program, and HMI configuration before NCU replacement to minimize downtime.

Check Power Supply Voltages

Measure 24VDC supply voltage at NCU terminals. Verify voltage stability within ±5% tolerance and check for ripple using oscilloscope.

Voltage drops during spindle acceleration often indicate inadequate power supply capacity.

Verify System Grounding

Check cabinet grounding connections and measure resistance between NCU chassis ground and main earth ground. Should be <0.1 ohms.

Poor grounding can cause intermittent memory corruption and unpredictable system behavior.

Analyze Power Quality

Use power quality analyzer to check for voltage sags, surges, or harmonic distortion on incoming AC power during typical machine operation.

Install line reactors or isolation transformers if power quality issues are identified.

Reset Memory Test Parameters

Check MD11210 (memory test enable) and MD11200 (extended memory test) settings. Reset to default values and clear alarm memory.

Setting MD11210=0 temporarily disables memory test but should only be used for diagnostic purposes.

Reload NCK Software

Perform NCK software reload from CF card or network using HMI > Commissioning > Software > NCK Software Update procedure.

NCK software reload will reset all machine data - ensure complete backup exists before proceeding.

Verify CF Card Integrity

Check CF card for errors using HMI > Diagnostics > CF Card Test. Replace CF card if read/write errors are detected.

Use only Siemens-approved CF cards to prevent compatibility issues and data corruption.