Outdoor Unit Inverter Pcb Replacement Procedure - Mitsubishi Heavy Industries KXZ Series Service Manual

2.5 Outdoor unit inverter PCB replacement procedure

Since the following precaution is the important contents for safety, be sure to observe them.
●
WARNING and CAUTION are described as follows:
WARNING
!
CAUTION
Securely exchange the PCB according to this procedure.
●
If the PCB is incorrectly exchanged, it will cause an electric shock or fire.
Be sure to check that the power source for the outdoor unit is turned OFF before exchanging the substrate.
●
The PCB exchange under current-carrying will cause an electric shock or fire.
After finishing the PCB exchange, check that wiring is correctly connected with the PCB before power
●
distribution. If the PCB is incorrectly exchanged, it will cause an electric shock or fire.
Band the wiring so as not to tense because it will cause an electric shock.
●
Exchange the inverter PCB (Fig.1) according to the following procedure.
1
. Exchange the PCB after elapsing 3 minutes from power OFF
2
. In the situation that harnesses are connected to control PCB, be sure to measure voltage (DC) of two places ((A), (B))
and check that the voltage is discharged sufficiently . (Refer to Fig.2)
3
. Remove the harnesses from bands, clips and connectors on the control PCB. Then, remove the appointed screws (4 places)
of a controller.(Refer to Fig.3)
4
. Open main layer and measure voltage (DC) of a place (C) and check that the voltage is discharged sufficiently.
(Refer to Fig.4)
5
. Disconnect connectors from the inverter PCB (Refer to Fig.1), remove a snubber capacitor (Refer to Fig.4)
and harnesses ("P","N","U","V" and "W"), and exchange the inverter PCB then ..
In the situation of being opening main layer, do not press the controller from above. . It will cause the product deformation or injury.
6
. Match the setting of switches (JSW10, 11) of new PCB with former PCB.
7
. After exchanging the inverter PCB, install the snubber capacitor to power transistor (Refer to Fig.5), and reconnect
the connectors and the harnesses as before. (Confirm the
Be careful not to pinch the wiring at the time of closing main layer. The wiring is damaged, and it will cause a short circuit or fire.
CNA
Fig.1 Parts arrangement view of inverter PCB
Precautions for Safety
Indicates an imminently hazardous situation which will result in death or serious injury
if proper safety procedures and instructions are not adhered to.
Indicates a potentially hazardous situation which may result in minor or moderate injury
if proper safety procedures and instructions are not adhered to.
CNR
117
–
WARNING
CAUTION
.
.
connectors are not half inserted
CNI2
JSW10,11
After elapsing 3 minutes from
.
Parts No
Connectors are not half inserted
–
'14 • KX-SM-221
PCB012D057A
.)
power OFF