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ErrorLib — Industrial Fault Code Library

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306

Motor Overheat (OHAL)

Fanuc · Alpha i series AC Servo Motor

What does 306 mean?

The motor has overheated (OHAL), causing its internal thermostat to trip. This indicates that the motor's operating temperature has exceeded safe limits, potentially due to severe conditions or high ambient heat.

Common Causes

  • Motor overheating due to excessively strict operating conditions (e.g., heavy load, high speed, high duty cycle).
  • Excessively high ambient temperature surrounding the motor, preventing adequate cooling.
  • Motor's internal thermostat has tripped due to overtemperature.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Investigate and reduce the severity of motor operating conditions.

  2. 2

    Verify that the ambient temperature around the motor is within specified limits.

  3. 3

    If the alarm recurs after the motor has cooled down, replace the faulty motor or servo amplifier.

Browse all codes in this manual (60)
Verified technical data. Last updated: April 2026

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000Power-Down Required Parameter011Zero Feedrate Specified013Maximum Feedrate Zero
Source: Fanuc Alpha i series AC Servo Motor
Open Manual (Page 224)Search more codes in this manual