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|  MIL-C-21679(NOrd)
4.6.3
Completed mechanism tests.
CAUTION: The mechanism may be seriously damaged
by over-winding. Do not use any method of winding
except the key provided with the mechanism. In-
sert the winding key and wind only until the arrow
points to the START mark on the clock housing. Do
`not wind beyond this point.
4.6.3.1 Insulation resistance. - A test potential of
500 20 volts d-c shall be applied between circuits speci-
fied in 3.2.5.1. The insulation resistance shall be not
less than 50 megohms as measured with test item 4.4.1.1 (a).
To facilitate inspection, the mechanism may be tested at
room ambient conditions. If the insulation resistance at
ambient conditions falls below the resistance specified, the
mechanism may be retested at a temperature of 77 2 F
with a relative humidity of 75 * 5 percent after being sub-
jected to these test conditions for a period of 24 hours.
4.6.3.2 Operation test. - With the mechanism operating,
manually rotate it. from the position with mounting studs
vertically down to the position with mounting studs vertic-
ally up. Then with the mounting studs horizontal, manually
rotate the mechanism through 360 degrees. Rotation in each
case shall not exceed 2 rpm. Any clock which fails to op-
erate throughout the test shall be considered defective.
4.6.3.3 Verge adjustment and test. - Adjustment of the
verge, as specified in 3.2..5.3, shall be made by bending
the verge. Testing of the verge shall be accomplished in the
following. manner. With the mainspring wound, the verge
assembly shall be unlocked but shall be restrained with light
finger pressure applied to the verge top weight. The verge
shall be oscillated very slowly while applying light pressure
toward the escape wheel along the line of centers. The drop
action for the incoming and departing pallets of the verge
and for each tooth of the escape wheel shall be observed
visually. The locking action at both locking faces of the
verge shall also be observed. Any mechanism which fails to
demonstrate proper verge adjustment, as specified in 3.2.5.3,
shall be considered defective.
4.6.3.4
Locking and starting tests.
4.6.3.4.1 Starting force. - A force not greater than
2 1/4 pounds shall be applied to the plunger assembly and
shall unlock the verge assembly allowing the mechanism to
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