Caterpillar 3412C — Insulation - Test
Testing & diagnosis · Generator main stator winding
For the Caterpillar 3412C, from the Caterpillar owner's manual.
Applies to: Caterpillar 3412C, Caterpillar 3412C engine
Before you start
- Megohmmeter applies high voltage; discharge leads before touching
Procedure
- Take the generator out of service; inspect for moisture.
- Discharge the capacitance of the windings.
- Disconnect T0 from ground and regulator sensing leads 20, 22, 24.
- Connect megohmmeter RED lead to ground, BLACK lead to T0.
- Set 500 V for units 600 V or less; else 1000 V.
- Apply voltage; observe readings at 30 and 60 seconds.
- Record the 60 second reading, temperature and humidity.
- Switch megohmmeter OFF to discharge the leads.
Tools required
- 9U-6003 Megohmmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Test every three months in a humid environment
- Test every six months in an enclosed area
Full service-parts list: Caterpillar 3412C →, Caterpillar 3412C engine →
Source: Caterpillar owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.