Hitachi RAS-20CNHZ2 - Trouble Shooting

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TROUBLE SHOOTING
MODEL RAM-50CNHZ2
PRECAUTIONS FOR CHECKING
Power source
1ø220V-240V, 50Hz
+
–
+
–
–
–
ACT-MODULE
+
–
+
–
L
C
D
N
Compressor motor
Indoor unit
electric parts
Control
P. W. B .
DC35V
0V
(0V)
MAIN P.W.B.
Power module
a
b
M
System power module
1. Remenber that the
0V line is biased to
155-170V in
reference to the
ground level.
2. Also note that it takes
about 10 minutes
until the voltage fall
after the power switch
is turned off.
DANGER
Across a – b (0V line)....................
Across a – ground.............................
Across b (0V line)– ground..............
approx 360V
approx 155-170V
approx 155-170V
When using an
oscilloscope, never
ground it. Don't forget
that high voltages as
noted above may
apply to the
oscilloscope.
DANGER
Always keep your hands
and metallic things away
from the enclosure of the
oscilloscope.
DANGER!
Don’t install
the ground
line.
Oscilloscope
Outdoor unit P.W.B.