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Check Axis Movement Manually

With drives disabled, manually move the axis to check for binding, excessive friction, or mechanical obstructions.

Ensure machine is in safe state and drives are properly disabled before manual movement

Inspect Mechanical Components

Check ball screws, linear guides, couplings, and gearboxes for wear, damage, or contamination that could increase load.

Look for metal chips or debris in the way covers - often indicates excessive wear

Verify Load Parameters

Check MD32000 (moment of inertia) and MD32010 (load moment) settings match actual mechanical configuration.

Use SINUMERIK's auto-tuning function to recalculate optimal load parameters

Monitor Current Draw

Use HMI Service → Drive → Diagnosis to monitor real-time current consumption during axis movement and compare to MD32110 rated current.

Current should typically stay below 80% of rated current during normal operation

Verify Current Limit Settings

Check MD32200 (maximum current) is properly set for your motor specification, typically 150-200% of MD32110 (rated current).

Consult motor nameplate data to verify current ratings match SINUMERIK parameters

Review Controller Gains

Access HMI → Parameters → Machine Data → Axis and verify MD32300 (Kv factor) and position loop gains are appropriate for the mechanical system.

Incorrect gains can cause instability and excessive current draw

Check Feed Forward Settings

Verify MD32610 (velocity feed forward) and MD32620 (acceleration feed forward) are optimized to reduce following error and current demand.

Use SINUMERIK's optimization functions under HMI → Service → Drive → Optimization

Validate Motor Data

Confirm MD32110 (rated current), MD32120 (rated voltage), and MD32130 (rated speed) match the actual motor specifications exactly.

Even small discrepancies in motor data can cause significant current limiting issues

Check Motor Winding Resistance

Measure motor winding resistance with drives powered down and compare to motor specifications or other identical axes.

Ensure proper lockout/tagout procedures before electrical measurements

Verify Encoder Signals

Use HMI → Service → Drive → Encoder to check encoder signal quality, track signals A/B/Z, and verify proper commutation.

Look for irregular signal patterns or missing pulses that indicate encoder damage

Inspect Motor Connections

Check motor power and encoder cable connections for looseness, corrosion, or damage that could cause signal degradation.

Pay special attention to encoder shield grounding - poor grounding causes noise and current issues

Test Motor Isolation

Measure insulation resistance between motor windings and ground using megohm meter - should be >1 megohm.

Low insulation resistance indicates motor winding damage and potential safety hazard

Monitor DC Bus Voltage

Check DC bus voltage in HMI → Service → Drive → Power section - should be stable at approximately 565V DC for 400V AC supply.

Voltage drops during axis movement indicate power supply or regeneration issues

Check Drive Module Status

Review drive diagnostics for power module faults, overtemperature conditions, or IGBT status indicators in the drive diagnostic screens.

Drive module failures can cause dangerous conditions - replace immediately if faults detected

Verify Power Supply Capacity

Calculate total power requirements for all axes and compare to power supply rating, including regenerative power handling capability.

Consider adding regenerative resistors if frequent deceleration causes DC bus overvoltage

Inspect Cooling System

Check drive module cooling fans, heat sinks, and cabinet ventilation to ensure adequate thermal management.

Overheated drives reduce current capacity and trigger protective limiting functions

Review Part Program

Analyze NC program for excessive feed rates, tight radius moves, or rapid axis reversals that could cause high current demand.

Use SINUMERIK's program simulation to identify problematic moves before machining

Check Acceleration Limits

Verify MD32300 (maximum axis acceleration) and MD32310 (maximum axis jerk) are set appropriately for the mechanical system capabilities.

Excessive acceleration settings can damage mechanical components and cause current limiting

Optimize Feed Rate Settings

Review programmed F values and ensure they are compatible with axis dynamics and current capacity limitations.

Use adaptive feed rate functions to automatically optimize feed rates based on cutting conditions