(3) Press 400 Hz GEN T1 circuit breaker to IN
position.
(4) Set DC BACK-UP to ON. Digital voltmeter
will indicate approximately 23 vdc. If not, see
troubleshooting Table 4-7.
(5) Disconnect test equipment from test set.
e. Lump Circuit.
(1) Pull 400 Hz GEN T1 circuit breaker to OUT
position and set GEN/PMG VOLTS switch to T1.
(2) Connect test equipment as shown in Figure 4-2
(DC power supply ON or OFF). Lamps can be checked
with 28 vdc or 115 vac applied.
(3) Pull 400 Hz GEN T1 circuit breaker to IN posi-
tion and adjust AC power supply to 115 ac.
(4) Press all test indicator lamps. Indicator lamps
will light when pressed. If not, see troubleshooting
Table 4-7.
(5) Disconnect all test equipment.
f. Voltage Regulator Test Circuit.
(1) Pull 400 Hz GEN T1 circuit breaker to OUT
position.
(2) Set all test switches to down or OFF except
TEST SELECT to START TEST and GEN/PMG
VOLTS to T1.
(3) Connect J1 pins W and X together with jumper
lead and connect digital voltmeter between J1 pins f (+)
and h (–) on test set.
—
(4) Connect test equipment as shown in Figure 4-2
(DC power supply not connected).
(5) Press 400 Hz GEN T1 circuit breaker to IN
position and set BACK-UP DC power and GEN switches
to ON.
(6) Reset and SIM CONT indicator lights will light
and digital voltmeter will indicate approximately 22.3 vdc.
If not, see troubleshooting Table 4-7.
(7) Disconnect all test equipment and set test set
switches to down or OFF.
(8) Remove jumper lead from J1 pins W and X.
g. FIELD AMPS/REG VOLTS Meter Circuit.
(1) Pull 400 GEN T1 circuit breaker to OUT
position.
(2) Connect jumper lead to J1 connector between
pins g and X and set DC BACK-UP switch to ON.
—
TM 55-4920-410-13&P
(3) Connect test equipment as shown in Figure 4-2
(DC power not connected).
(4) Set 400 GEN T1 circuit breaker to IN position
and READ REG BUS VOLTS-FLD CUR switch to UP
position.
(5) Adjust AC power supply for a 30V indication on
FIELD AMPS/REG VOLTS meter. If not, see
troubleshooting Table 4-7.
(6) Disconnect jumper lead from J1 pins g and X
and remove AC power supply. Connect test equipment as
shown in Figure 4-4.
(7) Set READ BUS VOLTS-FLD CUR switch to
down position and TEST SELECTOR to START TEST.
(8) Adjust DC power supply for a 1 AMP indication
on FIELD AMP/REG VOLTS meter. Digital voltmeter
will indicate between 8 and 12 mvdc. If not, see
troubleshooting Table 4-7.
(9) Disconnect all test equipment and set test
switches to down or OFF position.
h. CT Current Meter and Current Transformer
Circuit.
(1) Connect test equipment as shown in Figure 4-5.
Observe that 400 GEN T1 circuit breaker is OFF.
(2) Position test set controls as listed in (a) through
(e) below:
(a)
(b)
(c)
(d)
(e)
(3)
adjust dc
(4)
TEST SELECT switch to AØ.
CT CUR READ switch to UP.
GEN/PMG VOLTS switch to T1.
400 GEN T1 to IN position.
All Other Switches to down or OFF.
Adjust resistance standard to 3300 ohms and
power supply to 28 vdc.
Adjust AC power supply for 115 vac at 400 Hz
as indicated on GEN/PMG VOLTS and FREQUENCY
Meters. CT TEST CURRENT meter will indicate
between 0.9 and 1.1 made. If not, see troubleshooting
Table 4-7.
(5) If voltage is checked at each TEST SELECT
switch BØ GEN CT-J1 pin L, CØ GEN CT-J1 pin M, AØ
DPCT-J1, BØ DPCT-J1 pin P, CØ DPCT J1 pin Q results
will be as indicated in (4) above. If not, see troubleshoot-
ing Table 4-7.
(6) Disconnect all test equipment from test set.
(7) Connect test leads to J1 connector H and G to
digital voltmeter and connect DC power supply leads to
J1 connector pins S ( -) and J (+).
(8) Set TEST SELECTOR to FL REG. Digital
voltmeter will indicate approximately 3 ohms. If not, see
troubleshooting Table 4-7.
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