What causes Haas Automation Next Generation Control (NGC) alarm 108?

1. Feeds and speeds too high for the cut: Reduce feeds and speeds and watch the axis load in the position display. 2. Dull or broken tool: Inspect the tool and replace it if worn or damaged. 3. Mechanical blockage or binding in the axis: Make sure the axis has a clear path of travel. On a rotary, Haas’s check is E-stop, disconnect air, then try to turn the wormshaft or transmission pulley by hand; if it will not turn, the unit is bound. 4. Brake not releasing (rotary brake solenoid, pinched air or hydraulic line, or a linear-axis motor brake): Troubleshoot the brake solenoid and air or hydraulic line on rotaries; on linear axes Haas’s brake check is 20–30 VDC across the brake leads after RESET and none in E-stop. 5. Servo amplifier problem: Troubleshoot the axis servo amplifier per Haas’s servo amplifier guide.

Haas Alarm 108 Axis Servo Overload: Causes and Checks

Technical review pending. This guide is based on the cited manufacturer documentation; check it against the manual for your exact model and firmware before acting.

Alarm 108 AXIS SERVO OVERLOAD on a Haas NGC means the load on an axis motor was over 100% for a period of several seconds or even minutes. The number in front of the period names the axis: 1.108 is X, 2.108 Y, 3.108 Z, 5.108 A, 6.108 B and 7.108 C.

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When it happens

Heavy cutting on one axis
Long moves against a drag (way covers, chips, brake)
Rotary axis clamped or bound while commanded

Likely causes and checks

1Feeds and speeds too high for the cut

Points to it: Alarm during heavy cuts; axis load meter high for the whole pass.
Check: Reduce feeds and speeds and watch the axis load in the position display.

2Dull or broken tool

Points to it: Load rises over the life of the tool; alarm after a tool chipped.
Check: Inspect the tool and replace it if worn or damaged.

3Mechanical blockage or binding in the axis

Points to it: Load high even on air moves; chips in way covers; noise when jogging.
Check: Make sure the axis has a clear path of travel. On a rotary, Haas’s check is E-stop, disconnect air, then try to turn the wormshaft or transmission pulley by hand; if it will not turn, the unit is bound.

4Brake not releasing (rotary brake solenoid, pinched air or hydraulic line, or a linear-axis motor brake)

Points to it: High load from the first move after servo-on; on a rotary, air line damage or clamp not releasing.
Check: Troubleshoot the brake solenoid and air or hydraulic line on rotaries; on linear axes Haas’s brake check is 20–30 VDC across the brake leads after RESET and none in E-stop.

5Servo amplifier problem

Points to it: Mechanics and cutting conditions are normal but the alarm repeats on one axis.
Check: Troubleshoot the axis servo amplifier per Haas’s servo amplifier guide.

Telling it apart

Alarm 103 AXIS SERVO ERROR TOO LARGE means the axis could not reach the commanded position at all; 108 is sustained high load while it can still move.
Alarm 174 TOOL LOAD EXCEEDED is the user-set tool load limit (Advanced Tool Management), not the motor overload.
On the Classic Haas Control the overloads had separate numbers per axis (108–111, 188, 271, 674); on the NGC they are all 108 with an axis prefix.

Evidence to collect

Full alarm number with axis prefix
Axis load reading during the cut and on an air move
Tool condition
Brake and air-line condition on rotaries

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Haas Automation Next Generation Control (NGC) alarm 108: AXIS SERVO OVERLOAD