Power Circuit - Hitachi RAK-25NH4 Service Manual

Model RAC-25NH4, RAC-35NH4, RAC-50NH4

1. Power Circuit

TERMINAL
BOARD
25A FUSE
NF COIL1
L
SURGE-
ABSORBER
a
N
CT1
C009
L001
0V
0V
DIODE
STACK 2 (RC2)
This circuit full-wave rectifies 220-230V AC applied between terminals L and N, and boosts it to a required
voltage with the active module, to create a DC voltage.
The voltage becomes 260-360V when the compressor is operated
(1) Active module
The active filter, consisting of a reactor and
switching element, eliminates higher
harmonic components contained in the
current generated when the compressor is
operated, and improves the power-factor.
(2) Diode stacks
These rectify the 220-230V AC from
terminals L and N to a DC power supply.
COIL
POWER RELAY
R007 R008
ICP RELAY
JW6
L002
R002
C014 C012
C007
C015 C013 C008
REACTOR
L1 L2
SPM2
DIODE
STACK 1 TB7 TB6
TB8
(D25VB60)
b
TB2
Fig. 1-1
< Reference >
In case of malfunction or defective connection:
Immediately after the compressor starts, it may stop
due to "abnormally low speed" active error, etc.
The compressor may continue to operate normally,
but the power-factor will decrease, the operation
current will increase, and the overcurrent breaker
of the household power board will probably activate.
In case of active module faulty or defective
connection:
Although the compressor continues to operate
normally, the power-factor will decrease, the
operation current will increase, and the overcurrent
breaker of the household power board will probably
activate.
< Reference >
If diode stack 1 is faulty, the compressor may stop
due to "lp", "anbormally low speed", etc. immediately
after it starts, or it may not operate at all because
no DC voltage is generated between the positive e
and negative d terminals.
If diode stack 1 is faulty, be aware that the 25A
fuse might also have blown.
If diode stack 2 is faulty, DC voltage may not be
generated and the compressor may not operate at
all. Also, be aware that the 3A fuse might have
blown.
– 67 –
Vd
N1
P1
TB10
U
TB11
V
TB12
W