TM 5-6115-586-34
and 392
to 408 Hz for 400 Hz system within three
(h) lnstall thermocouple in boss provided on
seconds.
engine tailpipe section. Cheek tailpipe temperature circuit
by using the Brown indicator and unit thermocouple.
(4) Check air-intake door interlock switch as
Adjust so that unit thermocouple reads within +/- 25 F
follows.
(14C) of indicator reading.
(a) Attempt a start with air-intake door closed.
Unit shall not start.
f. Electrical System Checks.
Perform electrical
system checks as follows:
(b) While operating, press intake door interlock
switch and hold momentarily. Unit shall shut down.
(1) Operate unit in the following sequence at
(5) With unit operating and 400 Hz main
steadv-state loads at zero. 100, zero, 50 and 100 percent
contactor switch in OPEN position, actuate 400 Hz output
rated loads of 0.8 PF. Perform test on both 60 Hz
contactor switch to CLOSE-RESET and release. Using a
generator and 400 Hz generator. Log on each data sheet
volt-ohmeter, set on 300 vac scale, check voltage at J7
voltage, frequency and percent load it each load point for
and J8, 400 Hz output receptacle and across pins A,B,C
each phase of the 400 Hz generator and for each leg and
and E. There shall be no voltage indicated.
L-L of the 60 Hz generator.
(6) With 400 Hz main contactor switch in
(2) Perform voltage regulation check
(step
OPEN position and air-conditioning control circuit breaker
load application and removal) as follows.
pushed in, rotate ac mode select switch to VENY COOL
AND HEAT. In the VENT, COOL AND HEAT Modes,
Note
there shall be no power, ac or dc, applied to air-
The 10 kw, 60 Hz load can be
conditioning system. No fan or compressor shall start nor
applied directly through output
shall load control or heating flow-control valves open in
receptacles. To apply 90 kw. 400
the HEAT mode.
Hz loads. attach extra power loads
(7) Perform emergency dc output and standby
to terminal board on the air
receptacle output check as follows:
conditioning panel. Apply 30 kw to
power output and 60 kw to terminal
board connection.
check across pin A (+ ) of J5 and J6, 60 Hz output
receptacle and pin D (-) of J7 and J8, 400 Hz output
(a) Apply a step load of 10 kw at 0. 8 PF to 0it)
receptacle and also across pin 1 (+ ) and pin 2 (-) of J 1
Hz generator. Allow voltage to stabilize, then remove 10
dc standby receptacle. This test can be made while
kw load.
performing 400 Hz output overload sensor trip test, or by
placing 400 Hz output contactor switch in center position
(b) Using a 90 kw at 0. 8 PF load, repeat
with 400 Hz main contactor closed. When 400 Hz output
paragraph f. step (2), (a) above for 400 Hz generator.
contactor trips, there should be a 24 vdc indication
between J5-A and J7-D, J6-A and J8-D and J1-1 and J1-
(3) Unit shall meet the following electrical
2.
requirements.
(b) With same meter connection as in (a)
(a) Voltage variation shall not exceed 2. 5
above and when performing underfrequency trip check or
percent from no-load to full-load as set throughout entire
any of the other protective device checks that trip 400 Hz
load range and -1 percent at any fixed load.
generator, check for voltage indication. Each check point
(b) Upon application or removal of rated load
shall indicate 24 vdc.
I10 kw at 0. 8 PF), voltage shall not vary sufficiently to
(c) With same meter connections as in (a) and
cause generator protective panel to trip generator off the
(b) above and when performing any of the protective
line.
device checks that trip 60 Hz generator, observe meters
(c) Upon application or removal of 90 kw at 0.
for voltage indication. When 60 Hz contactor trips, there
8 PF, voltage shall not vary sufficiently to cause
shall be 24 vdc showing on meter attached to pin A of J5
protective panel to trip generator off the line.
or J6.
(8) Place all circuit breakers and switches in
percent for (0' Liz system and 392 to 408 Hz for 400 Hz
normal position for starting and proceed as follows.
system for all steady-state load conditions.
(a) Close air-intake door. Reconnect 24 vdc to
(e) Transient-frequency limits for sudden
J 1. Unit shall not start. Disconnect 24 vdc from J1.
application or removal of 10 kw at 0. 8 PF shall be within
(b) Open air-intake door. Reconnect 24 vdc to
4+/- 3 percent for 60 Hz system. Transient-frequency
J1. Unit shall start. At 95 percent governed speed, 24
limits for sudden application or removal of 80 kw at 0. 8
vdc signal from J1 shall cease and all contactors shall
PF shall be 390 to 410 Hz for the 400 Hz system.
close. The 60 Hz and 400 Hz power shall be available at
(f) Transient-frequency shall return to and
output receptacles. With a volt-ohmmeter set at 300 vac,
remain within the range of 58 to 62 Hz for 60 Hz system
check pins B and C of J5 and J6 and pins C and D of J7
and J8.
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