TM5-6115-593-34 NAVFAC P-8-631-34 TO-35C2-3-463-2 volts per coil connected in series, to ground. (8) Bake armature as follows: (a) Vacuum impregnate until bubbling ceases. (b) Bake in 300°F (149°C) oven for 8 hours. (9) Type epoxy class F. 11-15.  FRAME AND STATOR COMBINATION. The generator stator is installed in the frame.  Eyebolts on the top of the frame provide a means of lifting.  The stator is mounted in an endbell positioned on the stator frame. a. Inspection. (1) Inspect stator frame for cracks and burred mating surfaces. (2) Inspect stator of generator for loose, frayed, or burned windings. (3) Inspect for missing or defective hardware. b. Test.  Disconnect all leads to completely isolate the winding. (1) Measure each of the six stator windings with a Kelvin double bridge.  Resistance shall be 1.691 to 1.725 ohms in each circuit. (2) Connect all stator leads together and measure between the leads and the generator frame with a megger.  To test insulation resistance, use a megohmmeter to measure the resistance between a winding and ground.  The insulation resistance of each of the windings should be at least 1 megohm at 77°F (25°C).  If this value is not met, clean or dry out the winding and repeat the test.  Replace if defective. NOTE Low insulation resistance may be caused by dirt or excessive moisture.  Insulation failure may be caused by wrong voltages, induced voltages caused by opening field circuits too quickly, oil and grease, high temperatures, or excessive vibration. (3) Perform the following stator winding short circuit test: (a) Use an outside-type growler, and test each coil in the stator.  Position the growler in the stator and hold a thin metal strip, similar to a hacksaw blade, parallel to the core slots. (b) Energize the growler and explore the core surfaces approximately one pole distance on each side of the growler. Continue testing one core slot at a time until all coils are tested.  If the winding is shorted, the metal strip will vibrate when held over the slot containing the faulty coil. (c) If the above test is not met, proceed with repair procedure. c. Replacement.  The generator stator core is not to be removed from the stator frame because the concentricity between bore and rabbit fits would be disturbed and cause voltage modulation problems. d. Repair. (1) Repair frayed insulation on leads connected to the stator windings by covering with tape or sleeving. (2) Replace eyebolts if defective. 11-38