Figure A-3. Enlarged View Showing Typical Spring Installation
brushes (11). Torque screws to 40-46
inch-pounds. Threads of two screws used
to fasten negative leads to end bell (30)
Idle motor at 8-12 volts for a minimum of one
are to be coated with sealing compound
hour or until a minimum of 80 percent brush
primer and sealant.
seat across the face of the brush is obtained.
C. Dielectric Strength Test.
15. Install spacer (10), washer (9), fan (8),
washer (7) and screw (6), torqued to 100
While motor is still warm from run-in, lift the
negative brushes and apply 500 volts AC
16. Install washer (5) and screw (4) torqued to
between positive terminal and frame. There
shall be no evidence of failure as indicated on
standard test equipment.
17. Install cover (3) and two screws (2).
Install filter (1) and the remaining four
screws (2). Torque all six screws to 12-15
The dielectric strength test must be
compound primer and sealant on the
conducted prior to the installation of the
radio noise filter or with the radio noise
filter electrically insulated from the
A. Test Equipment.
D. Load Test.
Only standard equipment is required for testing
Mount motor on suitable test stand. Set the
the unit. This should include a 27 volt DC
voltage and torque load according to the values
power source and a test stand suitable to meet
listed in the table. Measure and record values