Hitachi RAS-18YH4 - Trouble Shooting

– 70 –
TROUBLE SHOOTING
PRECAUTIONS FOR CHECKING
RAC-18YH4
WARNING
WARNING
Always keep your hands
and metallic things away
from the cabinet.
DANGER!
Don't install
the ground
line.
When using an
oscilloscope, never
ground it.
Don't forget that high
voltage as noted in
the figure above may
apply to the
oscilloscope.
Remember that
voltage of 175 V is
applied to the 0V line
on the P.W.B. or the
like as shown in the
right diagram.
Indoor Controller
O
utdoor C
ontroller
Power Sw
itch
Point
400 F
I.P.M
Com
pressor
motor
Point
line
Control
P.W
.B.
C
ontrol
P.W
.B.
V
oltage at point A
G
round voltage
Grounding
350V
P
oint B (0V
line)
Power
inlet