MIL-PRF-39002C
4.6.13 Moisture resistance (see 3.18). Resistors shall be tested in accordance with method 106 of MIL-STD-202.
The following details and exceptions shall apply:
a.
Mounting: On a stainless-steel panel of sufficient size to extend beyond the resistor extremities, and in such
a manner as to allow electrical connections to be made to the terminals.
b.
Initial measurement: Immediately following the initial drying period, total resistance shall be measured as
specified in 4.6.2.1.
c.
Polarization and loading voltage: The resistors shall be divided into two equal groups; one group shall be
subjected to polarization and the other group to load.
(1) Polarization: During step 1 to step 6 inclusive, a 100-volt dc potential shall be applied with the positive
lead connected to the resistor terminals tied together, and the negative lead connected to the mounting
plate.
(2) Loading voltage: During the first 2 hours of step 1 and step 4 inclusive, a dc test potential equivalent to
100-percent rated wattage shall be applied to the resistors.
d.
Final measurements: Upon completion of step 6 of the final cycle, the resistors shall be held at the high
humidity condition. While the resistors are still in the humidity chamber, the total resistance shall be
measured as specified in 4.6.2.1.
Upon removal from the chamber, resistors shall be permitted to dry for 30 minutes ±15 minutes at room
ambient conditions. The sample units shall not be subjected to forced circulating air during this test.
Insulation resistance and independent linearity tolerance shall be measured as specified in 4.6.9 and 4.6.8,
respectively.
e.
Examination after test: Resistors shall be examined for evidence of mechanical damage.
4.6.14 Acceleration (see 3.19). Resistors shall be tested in accordance with method 212 of MIL-STD-202. The
following details and exceptions shall apply:
a.
Special mounting means: Resistors shall be mounted by their normal mounting means with their bodies
restrained from movement on an appropriate fixture. The mounting fixture shall be constructed in such a
manner as to insure that the mounting supports remain in a static condition with reference to the
acceleration-test table. Resistors shall be mounted in a plane so that the acceleration force is applied in
such a direction that the contact arm would tend to be forced either away from or along the resistance
element of the resistor.
b.
Test leads: Test leads used during the test shall be no larger than AWG size 22 stranded wire, so that the
influence of the test lead on the resistor will be held to a minimum. The test-lead length shall be no longer
than necessary.
c.
Test condition letter: A, 50 G.
d.
Measurements before acceleration: After mounting, total resistance and setting stability shall be measured
e.
Measurement during acceleration: Each resistor shall be monitored to determine electrical discontinuity of
the resistance element, and between the contact arm and element, by a method that shall at least be
sensitive enough to monitor or register automatically any electrical discontinuity of 0.1 milliseconds or
greater duration.
f.
Measurements after acceleration: Setting stability and total resistance shall be measured as specified in
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