Hitachi RAC-35NX2, Service Manual

Page: 181 / 194

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WARNING
[A. Main P.W.B.]
Remove four screws securing the main
P.W.B. to the cooling fins, and remove the
main P.W.B. from the cooling fins. 1
[B. Power P.W.B.]
Open the support latches and raise the
power P.W.B. in the direction of the arrow as
shown in Fig. A.
1
Open the support latches and raise
the main P.W.B. in the direction of
the arrow as shown in Fig. A. 2
<Direction of the main P.W.B. removal>
<Direction of the power P.W.B. removal>
PRECAUTIONS FOR SERVICING
Be sure that the power switch is turned off or the power cable is disconnected before servicing.
System Configuration of Outdoor Unit Electrical Parts.
<Main P.W.B. (M board)>
Contains a rectifier circuit and inverter module, their controlling microcomputer and
microcomputer peripheral control circuits. The board incorporates high and low current sections.
<Power P.W.B. (P board)>
Contains a switching power circuit, noise filter, power factor improvement circuit, etc.
The switching power circuit supplies power to electronic circuits on the main P.W.B. through
CN3.
When replacing any P.W.B., disconnect all the cables (including ground wires).
Removing the P.W.B.s.
The outdoor unit electrical parts consist of two P.W.B.s as shown in the figure.
Fig. A
Open these support latches to
remove the power P.W.B.
Open these support latches to
remove the main P.W.B.
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