Haas 901 - PARAMETERS HAVE BEEN LOADED BY DISK | Haas CNC Alarm
Haas 901 Motor Overcurrent alarm occurs when the drive detects excessive current draw from a servo motor, typically exceeding the programmed current limit parameters. This protection mechanism prevents motor and drive damage from mechanical overloads, binding conditions, or electrical faults in the motor circuit.
HaasProgram/G-codeAdvanced20-45 minutes
901
Haas 901 - PARAMETERS HAVE BEEN LOADED BY DISK | Haas CNC Alarm
PARAMETERS HAVE BEEN LOADED BY DISK
This informational message confirms that machine parameters have been successfully loaded from a USB drive or other disk storage device into the Haas control memory. The parameter file overwrites existing parameter values with those contained in the loaded file, which can significantly alter machine behavior, axis limits, spindle settings, and system configuration. The control requires acknowledgment before resuming normal operation to ensure operator awareness of the parameter change.
Root Cause Summary
Haas 901 Motor Overcurrent alarm occurs when the drive detects excessive current draw from a servo motor, typically exceeding the programmed current limit parameters. This protection mechanism prevents motor and drive damage from mechanical overloads, binding conditions, or electrical faults in the motor circuit.
Safety
Motor may be hot
Causes and Fixes
1
Emergency Stop and Visual Inspection
Press E-STOP and visually inspect all axes for obvious crashes, bent parts, or obstructions in the travel path.
Do not attempt to jog axes until obstruction is cleared
2
Check Axis Movement
With machine powered off, manually move each axis through its travel range to identify binding or unusual resistance.
X and Y axes should move smoothly with moderate hand pressure when drives are disabled
3
Inspect Way Covers and Chip Load
Remove way covers and clean excessive chip buildup that may be causing binding in the linear guides or ballscrews.
Pay special attention to the X-axis way covers which commonly accumulate chips
4
Clear Alarm and Test Jog
Power cycle machine, clear alarms with RESET, and carefully jog each axis at 1% rapid rate to verify smooth movement.
Keep hand on E-STOP during initial movement tests
1
Check Motor Cable Connections
Inspect motor power and encoder cables at both motor and drive ends for damage, loose connections, or contamination.
Look for oil contamination on encoder connectors which is common on Z-axis motors
2
Verify Motor Parameters
Access SETTING 84 (Motor Parameters) and verify motor type and current limit settings match the installed motor specifications.
Parameter 84 should show correct motor part number for each axis
3
Perform Motor Resistance Test
With machine off and motor cables disconnected, use multimeter to check motor winding resistance between phases (typically 1-3 ohms).
Disconnect all power before testing motor windings
4
Check Encoder Feedback
In MDI mode, jog axis slowly and monitor position feedback in CURRENT COMMANDS display for erratic or missing counts.
Encoder problems often show as position following errors before overcurrent alarms
1
Check Drive Status LEDs
Observe the status LEDs on the servo drive modules in the electrical cabinet for fault indicators (typically red LEDs).
Green LED indicates normal operation, red indicates drive fault condition
2
Verify Drive Cooling
Check that cooling fans are operating and heat sinks are clean. Measure cabinet temperature if possible.
Overheated drives can cause erratic overcurrent protection
3
Review Drive Parameters
Access SETTING 84 and verify current limit parameters are set correctly for the motor type and application load.
Current limits set too low can cause nuisance overcurrent alarms during normal operation
4
Swap Drive Test
If multiple identical axes, swap drive connections to isolate whether fault follows the drive or stays with the motor/mechanical system.
Only qualified technicians should perform drive swapping procedures
1
Review Active Program
Check the G-code program for excessive feed rates, rapid moves, or aggressive cutting parameters that occurred when alarm triggered.
Look for high feed rates combined with small radius moves which create high axis accelerations
2
Inspect Cutting Tool
Check tool condition for excessive wear, chipping, or buildup that increases cutting forces and motor loads.
Dull tools can double or triple the required cutting forces
3
Reduce Feed Override
Restart program with 25% feed override and gradually increase while monitoring for alarm recurrence.
Use CURRENT COMMANDS display to monitor actual motor loads during cutting
4
Optimize Program Parameters
Reduce feed rates, increase spindle speed, or decrease depth of cut to reduce axis loading in problematic program sections.
Parameter 19 (Max Cutting Feed) can limit maximum programmed feed rates
1
Check Input Power Quality
Measure incoming AC voltage at the main disconnect and verify it's within 208-240V ±10% specification with balanced phases.
Only qualified electricians should work on main power connections
2
Verify DC Bus Voltage
Check DC bus voltage at the drive power supplies (typically 325-340VDC) and look for excessive ripple or fluctuation.
Low DC bus voltage can cause drives to draw excessive current to maintain torque
3
Inspect Power Connections
Check all power connections in the electrical cabinet for tightness, corrosion, or overheating signs.
Loose connections create voltage drops that can cause overcurrent conditions
4
Test Under Different Conditions
Monitor for alarm occurrence patterns related to time of day, other equipment operation, or specific machine operations.
Power quality issues often correlate with facility electrical load changes
DIY Feasiblemedium confidence
Call a technician if:
·Drive replacement required
·Motor replacement needed
·Electrical cabinet work required
·Persistent alarms after mechanical issues resolved
Prevention
Regular way cleaning and lubrication
Monitor cutting tool condition
Use appropriate feeds and speeds
Keep electrical cabinet clean and well-ventilated
Perform regular motor cable inspections
Common Mistakes
Ignoring mechanical binding and only focusing on electrical causes
Setting current limits too low to avoid alarms
Not checking for chip buildup in way covers
Attempting to clear alarms without identifying root cause
Overlooking power quality issues in problematic facilities
