TM 9-4910-663-12
(b) The VAR position connects the meter circuit to the output
terminals of the dc variable volts circuit to measure the output
voltage of this circuit. When DC VOLTMETER OUTPUT VOLTAGE SELECT
switch (S11, fig 2-1) is set to VAR, the corresponding meter can be
used to measure dc voltages as applied with the DC VARIABLE POWER
SUPPLY 0-32 VDC (T5, fig 2-4) and DC VARIABLE VOLT switch (S10, fig
2-2) is placed to ON position.
(c) The RECT GEN position connects the meter circuit to G+ and
G- circuits of a dc generator test circuit, or to the plus and minus
outputs of the rectifier when ac ac/dc system is being tested.
(d) The EXT position connects the meter circuit to external dc
voltmeter binding posts (fig 2-2) to permit use of the meter for
measurement of dc voltages from sources outside the test stand.
(22) DC VOLTMETER OUTPUT VOLTAGE RANGE Switch (S12, fig 2-1).
This switch provides a means for selecting the desired range of the
associated meter, as required for the test being performed. The
switch positions are X1 (10 volts), X2 (20 volts), and X5 (50 volts),
with the multipliers applying to the meter scale indications.
(23) MILLIVOLT METER MILLIVOLT DROP PRESS TO READ Switch (S34,
fig 2-1). This switch, when actuated, connects the corresponding
meter to the test circuit. The switch is normally spring-loaded to
the off position to prevent the application of voltage to the meter.
A back-to-back diode prevents damage to the meter from momentary
overload.
(24) MILLIVOLT METER MILLIVOLT DROP RANGE Switch (S16, fig 2-1).
This switch is used to select either the X1 (900 millivolt) or X10 (9
volt) range of the associated meter, depending upon test requirements.
(25) DC AMMETER FIELD CURRENT RANGE Switch (S30, fig 2-1). This
switch is used to select the desired range of the associated meter.
This is accomplished by connecting the meter across the appropriate
external 50 millivolt shunt. This switch provides for the selection
of three ranges: X1 (5-0-5 amperes), X3 (15-0-15 amperes), and X6
(30-0-30 amperes).
(26) DC AMMETER LOAD & STARTER OUTPUT CURRENT BATTERY CHARGE
CURRENT RANGE Switch (S14, fig 2-1). This switch is used to select
the desired range of the associated meter. This is accomplished by
connecting the proper 50 millivolt shunt to the meter.
(27) DC AMMETER LOAD & STARTER OUTPUT CURRENT BATTERY CHARGE
CURRENT PRESS FOR BATTERY CHARGE RATE Switch (S15, fig 2-1). This
momentary switch, when pressed, connects the associated meter across a
50 millivolt shunt in the battery charge circuits of the test stand to
2-5