MIL-PRF-11767G(AT)
a. Between the winding terminals and the housing. If necessary winding internal
grounds could be disconnected.
b. Between the terminals of the relay assembly that are connected to the contact
points, and the relay housing.
The test potential shall be applied and reduced at a maximum rate of change of 250 V per
second. Duration of application of the test voltage shall be one minute for each winding and for
the circuit breaking, mechanisms. During this, time the relay assembly shall be observed for
evidence of short circuit or insulation break down. The relay assembly shall subsequently be
subjected to the tests specified in 4.10.1, 4.10.4, 4.10.5, and 4.10.7
NOTE:
Dielectric strength test could be conducted prior to final assembly of relay assembly.
NOTE:
Before high voltage is impressed upon any winding, terminal or other part of the relay
assembly, the construction should be carefully examined and the manufacturer's
internal circuit diagram for the device checked to determine where windings and other
parts are grounded. The appropriate low voltage circuit ground and circuit continuity
test should be made to assure that high voltage may not, through some unintended
circuit, cause serious damage, instead of determining insulation effectiveness.
4.10.4 Pick-up voltage. To determine conformance to 3.6.4, after the machine gun relay
has been temperature stabilized for 24 hours, it shall then be tested for 10 cycles (deenergize and
energize) to determine that the energized function is completed when a potential not in excess of
the pick-up voltage as specified in 3.6.4 is applied. A suitable indicating device shall be used to
determine that the contacts operate satisfactorily. Upon completion of this test, the test shall be
repeated at ambient air temperatures of -65 + 5°F, and +160 + 5°F.
4.10.5 Drop-out voltage. To determine conformance to 3.6.5, after the machine gun
relay has been stabilized, it shall then be energized with 28 Vdc. The voltage shall then be
reduced. The relay shall release to the deenergized position within the specified limits of drop-out
voltage as specified in 3.6.5. Repeat for 10 cycles. A suitable device shall be used to determine
that the contacts operate satisfactorily. Upon completion of this test, the test shall be repeated at
temperature of -65 + 5°F, and +160 + 5°F.
4.10.6 Coil current. To determine conformance to 3.6.6, the machine gun relay shall be
temperature stabilized. A voltage of 29 + 0.0, - 0.50 Vdc shall be applied between pins E and G
of the relay assembly, and the current flow determined within 10 seconds after application of coil
voltage.
4.10.7 Contact voltage drop. To determine conformance to 3.6.7, an average of
10 consecutive and individual readings shall be within the limits as specified in 3.6.7. Contacts
shall be caused to break and then to make the test current before each measurement. The machine
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