Hitachi Summit RAC-70YH5, Service Manual

Page: 57 / 102

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(3) Smoothing capacitor (C501, C502, C503)
This smoothes (averages) the voltage rectified by the diode stacks.
(4) Smoothing capacitor (C020)
This smoothes (averages) the voltage rectified by the diode
stack2. A DC voltage is generated in the same way as in
Fig. 1-3.
Voltage b side of C020 is about 330V.
(5) C001 to C003, C012 to C015, C007, C008, NF COIL1, COIL,
C22 ~ C25 absorb electrical noise generated during operation
of compressor, and also absorb external noise entering from
power line to protect electronic parts.
(6) Surge absorber, Varistor 1, 2, 3,
absorbs external power surge.
(7) Inrush protective resistor (R002, R003)
This works to protect from overcurrent when power is turned
on.
< Reference >
●
When inrush protective resistor is
defective, diode stack may
malfunction. As a result, DC voltage
is not generated and no operation can
be done.
●
Be careful to avoid an electric shock as a
high voltage is generated. Also take care
not to cause a short-circuit through incorrect
connection of test equipment terminals. The
circuit board could be damaged.
Fig. 1-3
Fig. 1-2
a
b
OV
OV
OV
Vd
DC voltage
(approx. 260-360V during operation)
Smoothing Capacitors
SPM2
0305E Pg 57-82 4/1/06, 10:59 AM 65