Hitachi RAC-18WPC, Service Manual, Page: 28 / 43

TROUBLE SHOOTING
MODEL RAC-18/25WPC
Note that the 0 V line of the
outdoor electrical parts and
the primary power circuit of
the indoor electrical parts
have voltages to ground as
illustrated in the right-hand
figure.
When conducting a check
with an oscilloscope or
something similar, do not
ground the oscilloscope.
Note that the oscilloscope
will be subjected to voltages
as illustrated in the figure
above.
Warning
Warning
Do not under any
circumstances get your
hand or metal part into
contact with the cabinet.
Danger!!!
Do not install
a grounding.
Inspection instructions
Power supply
P
o
w
er circuit
Control circuit Control circuit
Indoor fan motor
Outdoor Electrical Indoor Electrical
1
2
3
L
N
0V line
P
o
w
er circuit
Compressor
motor
Voltage between each
part and ground
Potential at
points
Potential at
points
320V
Potential at points
1 Φ 230V 50Hz
375 F
0V line
RAC-18/25WPC
28