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3-33. Rectifier
a. General. The rectifier is located on the center
right side of the junction box. It changes 30]-volt
alternating current to 30-volt direct current for
operation of the armature relays, compressor
start relay, time delay relay and solenoid valves.
b. Testing.
(1) Apply 208 volt. 60 Hertz, 3-phase power
to air conditioner.
(2) Check voltage between terminals 1 and
4. 30 vac should be indicated. Check voltage be-
tween terminals 2 and 3; 30 vdc should be indi-
cated. lf 30 vdc is not indicated, replace the recti-
fier. If 30 vac is not indicated between terminals 1
and 4 of rectifier (CRI), check for phase ABC at
phase sequence relay (K6), using a phase meter.
If phasing is incorrect, check unit incoming
power. If phasing is correct, check terminal 2 of
relay (K6) for 110 vac. If 110 vac is not indi-
cated, relay is defective and should be replaced. If
110 vac is indicated, check terminal 2 of XF1 for
110 vac. If 110 vac is not indicated. replace fuse-
Check for 110 vac at terminal 4 0f XF1. If 110
vac is not indicated, check terminal NO of circuit
breaker (CB1) for 110 vac. Reset circuit breaker
(CB1). Check for 110 vac at terminal 3 of XF1.
If 110 is not indicated, replace fuse. If 110 vac is
indicated at terminals 2 and 3 of XF1, check for
30 vac at terminals X1 and X2 of transformer
(T1). If 30 vac is not indicated, transformer is de-
fective and should be replaced.
Warning: Be careful when working with
high voltage. Contact with high voltage can re-
sult in serious injury or death.
c. Removal.
(1) Refer to figure 3-1 and remove the
lower front access cover.
(2) Remove cover from junction box (fig.
3-10).
(3) Refer to figure 3-13 and remove the rec-
tifier.
d. Installation. Installation is the reverse of re-
moval.
3-34. Transformer
a. General. The transformer reduces the 208
vac input electrical power to 30 (±3%) vac re-
quired by the rectifier. It is mounted on top right
external panel of the junction box, adjacent to
the control panel
b. Testing.
(1) Apply 208 volt, 60 Hertz, 3-phase power
to air conditioner.
(2) Check voltage between terminals X1
and X2 of transformer (T1). 30 vac should be in-
dicated, or transformer is defective and should be
replaced.
c. Removal
(1) Refer to figure 3–4 and remove lower
front access cover.
(2) Remove cover from junction box (fig.
3-10).
(3) Refer to figure 3–13 and remove trans-
former.
d. Installation. Installation is the reverse of re-
moval
3-35. Terminal Boards
a General
There are two terminal boards
mounted in the lower left corner of the junction
box. Electrical power is distributed from these
terminal boards to all electrical components of
the air conditioner. All terminal boards are re-
moved and installed in a similar manner.
b. Removal.
(1) Refer to figure 3–4 and remove lower
front access cover.
(2) Remove cover from junction box (fig.
3-10).
(3) Refer to figure 3-13 and remove termi-
nal board.
c. lnstallation. Installation is the reverse of re-
moval
3-36. Fan Motor
a. General. One double
provided for driving both
orator fans. The motor
extended shaft motor is
the condenser and evap-
operates in either low
speed or high speed, depending on the setting of
the two-speed motor switch. A pressure control
switch automatically controls the speed of the
fan motor when the two-speed switch is in the
LO-SPEED position by overriding the LO posi-
tion and switching to HI-SPEED when the con-
denser pressure reaches 400 psig; when the pres-
sure reduces to 350 psig, the motor speed is re-
turned to the LO position.
b. Testing.
(1) Remove condenser fan (para 3-24) and
baffle (fig. 3-16).
(2) 13215E9824-2, 0.125 in.
motor.
(3) Check for continuity across each combi
nation of two motor terminals; if continuity is
not indicated, the motor is defective and must be
replaced.
(4) Place one probe of the continuity tester
against the motor housing and the other probe
against each of the motor terminals, one at a
3-21
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