TM 9-4910-663-12
(g) While holding DC AMMETER LOAD & STARTER OUTPUT CURRENT
BATTERY CHARGE CURRENT PRESS FOR BATTERY CHARGE RATE switch (S15, fig
2-1) in the up position, increase BATTERY CHARGE CIRCUIT control (T3,
fig 2-4) until the desired rate of current is attained as indicated by
DC AMMETER LOAD & STARTER OUTPUT CURRENT BATTERY CHARGE CURRENT meter
(M3, fig 2-1) on the 0-50 (X1) ampere scale. Observe the battery
voltage also (M2, fig 2-1).
(h) CHARGE INDICATOR (DS8, fig 2-4) will remain illuminated
for the duration of charging time.
(i) Check rate of charge current periodically and adjust
current as necessary to maintain proper charge rate.
(j) After battery has been charged, be certain that the CHARGE
TIMER (MINUTES) control (TD1, fig 2-4) is at zero, rotate BATTERY
CHARGE CIRCUIT control (T3, fig 2-4) full counterclockwise, and posi-
tion MASTER LOAD DISCONNECTOR switch (S8, fig 2-2) and circuit breaker
switch (CB1, fig 2-5) to OFF.
Vibration Tachometer.
l.
(1) The vibration tachometer (34, fig 2-7) is of the vibrating
reed type and indicates speed when placed against the case of the
rotating apparatus.
(2) This tachometer is furnished for indicating speeds of start-
ers during the free running tests. Since the shaft of all starters is
not accessible for use of tips, this type of tachometer must be used.
(3) AS with any indicating device, it is advisable to calibrate
it with a "Strobotac" or some other accurate means. Under tests with
"Strobotacs" and other dial type speed indicating instruments, these
tachometers have been found to be very accurate.
(4) Since there is no adjustment on this tachometer except for
the manner in which it is placed against the case of the rotating
apparatus, the correction determined during calibration should be
marked on the carrying case.
(5) The vibration tachometer is used in the following manner:
(a) Hold the long edge of the tachometer firmly on the case of
the starting motor, being sure not to restrict the movement of the
reed.
(b) Move the tuning slide up and down the scale until the reed
reaches maximum vibration.
(c) Read the speed opposite the slide arrow,
(d) Further instructions for other uses of this tachometer are
included in the carrying case.
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