Hitachi RAS-25CNH1 - GENERAL TROUBLE SHOOTING; PRECAUTIONS FOR CHECKING

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TROUBLE SHOOTING
Model RAS-25CNH11 / RAC-25CNH11
PRECAUTIONS FOR CHECKING
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A
B
C
D
Outdoor unit electric parts
0V Line
Main P.W.B.
Compressor
motor
Indoor unit
electric parts
Control
P. W . B.
Power circuit
1,000
µF
ZZZ
µF
ZZZ
80
M
Power source from
an indoor unit 1 ∅,
220V, 50Hz
a
b
1. Remember that the
0V line is biased to
155-170V in
reference to the
ground level.
2. Also mote that it
takes about 10
minutes until the
voltage fall after the
power switch is
turned off.
Across a – b (0V line)....................
Across a – ground..........................
Across b (0V line)– ground............
approx. 311-260V
approx 1311V
approx 311V
When using an
oscilloscope, never
ground it. Don't forget
that high voltages as
noted above may
apply to the
oscilloscope.
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.