Mitsubishi Electric PUHZ-SW75VAA-SC Service Manual page 73

OPERATING PROCEDURE
4. Disassembling the electrical parts box (V model only)
(1) Remove the electrical parts box. (See Photo 3-1)
(2) Disconnect all the connectors on the controller circuit
board.
(3) To remove the controller circuit board, release it from the
support.
(4) Remove the cont base front fixing screws (3 for front/ 4 ×
10) to remove the cont base front.
(The cont base front is fixed to the electrical parts box
with a hook on the left side.)
(5) Disconnect all the connectors on the power circuit board.
(6) To remove the power circuit board, remove the power cir-
cuit board fixing screws (4 for front/ 3 × 12, 2 for front/ 4
× 18, and 1 for front 4 × 10), then release the board from
the support.
(7) Remove the reactor (DCL1, DCL2, DCL3) fixing screws (6
for rear/ 4 × 10) to remove the reactor, then disconnect
the connectors on reactor.
(8) Remove the thermistor <Heat sink> (TH8) fixing screws
(2 for front/ 3 × 12) to remove the thermistor <Heat sink>
(TH8).
(9) To remove the heat sink, remove the heat sink duct fixing
screws (6 for front/ 4 × 10), then slide the heat sink duct
sideways to remove the heat sink.
Note 1: When reassembling the electrical parts box, make
sure the wirings are correct.
5. Disassembling the electrical parts box (Y model only)
(1) Remove the electrical parts box. (See Photo 3-1)
(2) Disconnect all the connectors on the controller circuit board.
(3) To remove the controller circuit board, release it from the
support.
(4) Remove the cont base front fixing screws (3 for front/ 4 ×
10) to remove the cont base front.
(The cont base front is fixed to the electrical parts box
with a hook on the left side.)
(5) Disconnect all the connectors on the noise filter circuit board.
(6) To remove the noise filter circuit board, release it from
the support.
(7) Remove the cont base fixing screws (3 for front/ 4 × 10)
to remove the cont base.
(The cont base is fixed to the electrical parts box with a
hook on the left side.)
(8) Disconnect all the connectors on the converter circuit board.
(The converter circuit board is attached to the rear side of
the cont base.)
(9) To remove the converter circuit board, release it from the support.
(10) Disconnect all the connectors on the power circuit board.
(11) To remove the power circuit board, remove the power cir-
cuit board fixing screws (4 for front/ 4 × 14), then release
the board from the support.
(12) Remove the thermistor <Heat sink> (TH8) fixing screws (2
for front/ 3 × 12) to remove the thermistor <Heat sink> (TH8).
(13) Disconnect the connectors on reactor (ACL4), resis-
tor (RS) and capacitor (CK) first, then remove the fixing
screws of reactor, resistor and capacitor (4 for front/ 4 ×
10), and remove reactor, resistor, and capacitor.
(14) To remove the heat sink, remove the heat sink duct fixing
screws (6 for front/ 4 × 18), then slide the heat sink duct
sideways to remove the heat sink.
Note 1: When reassembling the electrical parts box, make
sure the wirings are correct.
OCH651A
Photo 4-1
Cont base front
Controller circuit board
Photo 4-3
Reactors
Photo 5-1
Cont base front
Controller circuit board
Photo 5-3
Converter circuit board
Photo 5-5
Heat sink
73
PHOTOS
Photo 4-2
Power circuit board
Photo 4-4
Thermistor <Heat sink> (TH8)
Heat sink
Photo 5-2
Noise filter circuit board
Cont base
Photo 5-4
Power circuit
Capacitor
board
Reactor
Thermistor <Heat sink> (TH8)
Resistor