Applicable Systems
GA Series Compressed Air System
Symptoms
Motor bearing temperature has exceeded the safe operating limit of 110C (230F). The Elektronikon triggers an immediate compressor shutdown to prevent stator winding damage.
Possible Causes
- Inadequate cooling airflow due to blocked motor cooling fan inlet or cowling
- Motor bearing grease degraded or over-greased causing excess friction
- Excessive load from a seized air end or high differential pressure across the element
Troubleshooting Steps
- Step 1: Check the motor cooling fan for debris, broken blades, or restricted intake grille
Clear obstructions and verify free rotation of the cooling fan - Step 2: Use an infrared thermometer to measure actual bearing housing temperature
If reading is below 90C but alarm persists, inspect the PT100 sensor and wiring - Step 3: Perform a hand-turn test on the air end coupling with the motor de-energized
If the air end does not turn freely, inspect the element for seizure or high back-pressure
How to Reset
Reset: The motor must cool below 85C before restart. Press Alarm Reset and wait for the automatic restart timer (configurable, default 3 minutes).
Common Replacement Parts
- 1616-7200-00: Motor bearing kit, GA 55-75 (SKF 6316 deep-groove ball bearing, C3 clearance)
- 2901-0516-00: Motor cooling fan blade (Glass-filled nylon, check for cracks)
Frequently Asked Questions
- Q: How long does the motor take to cool to 85C?
In normal ambient conditions (20-30C), allow 15-25 minutes after shutdown. Forced ventilation can reduce this to 8-12 minutes.
- Q: Can I override the motor temperature alarm to finish a batch?
No. The Critical alarm requires a hardware interlock reset and cannot be overridden via the operator panel without a factory-authorized password.
Source: Atlas Copco GA 30-90 Service Manual, 2950 1630 00
Category: Compressor