4.6.9 Dielectric strength. While the starter-generator is hot as a result
of testing, it shall withstand the following test voltage at commercial fre-
quency, applied between windings and between winding and frame, for the speci-
500V root mean square (ins) for 1 minute or
600V rms for 1 second
Radio noise filters may be removed or disconnected for this test.
4.6.10 Rip ple voltage-generator. Ripple voltage shall be determined by
means of a peak-reading vacuum tube voltmeter in series with a 4.0 microfarad
capacitor as shown on Figure 4. The generator shall be operated at speeds of
3,800, 6,000, and 8,100 rpm under conditions of no-load, half-load and rated-
load. A manually operated field rheostat shall be used in lieu of a voltage
Peak-voltage readings shall be taken with the voltmeter succes-
sively connected for each of the two polarities and the higher of the two
readings shall be not more than 1.5V. The voltmeter shall be an approved
type. At no time during this test shall a battery be used.
4.6.11 Cranking torque and speed. The starter shall be tested to determine
compliance with the minimum cranking torque and speed requirements specified
on Figures 1 and 2. An external resistance of 1.25 ohms shall be connected in
the shunt field circuit while conducting starter tests.
220.127.116.11 Conducted radio interference measurements. Unless otherwise
specified, conducted radio interference measurements shall be made between each
load of the starter-generator and negative grounded. The measurement shall be
made at the point of entry of leads to each unit, With a filter mounted and
properly connected to terminals A, B, and C, the conducted radio noise voltage
shall not exceed 2,000 microvolt (UV) over the 0.15 to 20.0 megacycles (me)
frequency range when operated at speeds ranging from 3,800 to 8,100 rpm under
conditions of no-load and rated-load.
18.104.22.168 Noise meters. The standard instruments for making radio inter-
ference measurements (0.15 to 20.0 mc) shall be in accordance with MIL-STD-826.
22.214.171.124 Bonding. The direct-current resistance between the commutator end
bell and face of mounting flange shall be not greater than 0.001 ohm.
126.96.36.199 Radiated interference. Radiated interference measurements in
accordance with MIL-STD-826 shall be conducted over the frequency range 0.15
to 1,000 mc.
4.6.13 Endurance-starter. The starter shall complete a 600-cycle endurance
test, as specified herein without damage to, or replacement of, component parts.
Each cycle shall consist of three consecutive phases, as shown in Table III.
188.8.131.52 After completion of this endurance test, the peak efficiency of
the starter shall not have decreased more than 5 per cent from the original
Total brush wear shall not have exceeded 20 per cent of the original
effective brush length on any one brush.