Hitachi RAS-25CNH2 Service Manual page 40

(3) Smoothing capacitor (C501)
This smoothes (averages) the voltage rectified by the diode stacks.
a
b
DC voltage
VD
(approx. 260-380V during operation)
(4) Smoothing capacitor (C501)
This smoothes (averages) the voltage rectified by the diode stacks.
A DC voltage is generated in the same way as in Fig. 1-3.
(5) C507, C508, C512, C513, C506, NF COIL1, NF COIL2, C502, C503, C514
These 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
These absorbs external power surge.
(7) Inrush protective resistor
This works to protect from overcurrent when power is turned on.
A
a
B
Fig. 1-2
Fig. 1-3
+
b
–
C501
OV
OV
Be careful to avoid an electric shock as a
G
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.
OV
< Reference >
When inrush protective resistor is defective,
G
diode stack may malfunction. As a result,
DC voltage is not generated and no
operation can be done.
– 43 –
+
VD
(DC voltage)
–