Hitachi RAM-18QH5E, Руководство по обслуживанию

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+
U
U
V
W
—
U
+
V
—
V
+
W
—
W
_
+
System power module
260V-360V
DC current (Id)
detection resistor
A
U coil
DC compressor
motor
V coil
W coil
B
●
Since current flows at point B only when U+ transistor is ON, the current waveform at point B becomes
intermittent waveform as shown in Fig. 3-3. Since current at point B is approximately proportional to the
input current of the air conditioner, input current is controlled by using DC current (Id) detection resistor.
<Reference>
If power module is detective, self diagnosis lamps on the control P.W.B. may indicate as shown below:
❈
From results of power module simple inspection (inspection mode when operated with compressor lead
disconnected), LD310 blinks four times about 2 seconds later: Unit has not entered the normal operation.
Fig. 3-4 Power module circuit (U+ is ON, V– is ON)
Self-diagnosis Self-diagnosis lamp and mode
lp (peak current cut) LD301
Abnormal low speed rotation
LD301
Switching incomplete LD301
Blinks 2 times
Blinks 3 times
Blinks 4 times
Table 3-1
SPM2
Smoothing Capacitors
(C501, C502, C503)
Reactor
Diode stack
(D25 VB60) Switching Power P.W.B.
(For Indoor P.W.B)
Service switch
Self-diagnosis lamps
(From left: LD301, LD302, LD303, LD304)
Control P.W.B.
Power P.W.B.
Terminal
Board (2p)
Terminal
Board (4p)