Hitachi RAW-35RHC - Page 45

This circuit full-waves recties 230 VAC applied between terminals L and N and boosts it to a required voltage with the
IPM to create a DC voltage.
The voltage become 300-330 V when the compressor is operated.

Main parts
Name Description
Intelligence power module (IPM)
A module that constitute by an inverter part.
In case of intelligence power module malfunction or connection failure
immediately after compressor starts, its may stop due to error of abnormal low
speed, switching failure, Ip stop and others.
Diode stack (DB601)
These rectify the 230 VAC from terminal L and N to a DC power supply.
If diode stack (DB601) are faulty, DC voltage may not be generated and the
compressor may not operate at all. Also be aware that the 15A fuse might have
blown.
Smoothing capacitors (C021-C022, 375 μF, 420 V) This smoothes (averages) the voltage rectied by the diode stack.
IGBT to improve e󰀩ciency (Q601)
It will improve the e󰀩ciency during compressor load become heavy when current
ow through the chopper period of Q601.
4 Electrical checks of main parts
Outdoor unit
SMGB0135 rev.0 - 06/2020
37
4