Hitachi RAM-60QH4 Manuel De Service page 70

(3) Smoothing capacitor (C501 , C502 , C503, 400μF , 450V)
This smoothes (averages) the voltage rectified by the diode stacks.
L
N
a
b
Vd
DC Voltage
（Approx. 300-330V during operation)
(4) Smoothing capacitor (C020, C021, 220μF, DC 250V)
This smoothes (averages) the voltage rectified by the diode stacks.
A DC voltage is generated in the same way as in Fig. 1-3.
a
SMOOTHING
CAPACITOR
SWITCHING POWER P.W.B.
REACTOR
SELF-DIAGNOSIS LAMPS
CONTROL P.W.B.
• 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
Fig. 1-4
terminals. The circuit board could be damaged.
b
＋ ＋
− −
Fig. 1-2
0V
0V
Fig. 1-3
SPM（SYSTEM POWER MODULE）
DIODE STACK
SERVICE SWITCH
Voltage between C020
– 82 –
＋
＋
Vd (DC Voltage)
−
−
2P TERMINAL BOARD
2P TERMINAL BOARD (2pcs.)
＋ −
side and C021 side is about 330V.