Pioneer WD Series, Руководство по обслуживанию

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Switching power output of power
source board CN4 CN4B on Intelligent
power module, and
CN4C on Power
factor correction
Communication signal of power
source board and module board CN5 CN5B on Intelligent
power module
Electronic expansion valve control
signal CN6 CN6B on Intelligent
power module
Electronic expansion valve socket CN7
Communication between power
source board and PFC board CN9 CN9C on Power
factor correction
Communication between nodule
board and PFC board CN8B(Module
board) CN8B on Power
factor correction
Base Auxiliary heating CN11
Cautions on Replacement of PCB Boards
1, Directive for Replacement of Inverter Module
When replacing Mitsubishi inverter module, the technician must take care on the operating process
for replacement of inverter module. Special care shall be taken to ensure the coating quality of
thermal grease. The detailed directive is as follows:
1. Before replacing the inverter module, make sure to eliminate the old thermal grease and
foreign particles with soft clean cloth before you can apply the new thermal grease. Always
use the thermal grease provided by the customer service department or the same silicone
grease as used in the factory. Never use any other product of poor quality. Operate in strict
accordance with the guideline.
2. Ensure that the thermal grease (silicone grease) is applied thin, flat and even. Use plastic
scraper to apply the grease. Firstly, place a tiny quantity of thermal grease at the center of the
place where the grease is to be coated. Then, use the plastic scraper to apply the grease at the
center slightly and evenly onto the entire surface to be treated. In consideration of the
deviation in the levelness of radiating fin, the thickness of thermal grease must be 0.1mm (for
small area) to 0.3mm (for large area), depending on the size of radiating area.
Note: The function of thermal grease is to fill up the gap and let the surface tightly adhered. It
is not true “the more the better".
3. Before placing the greased module flatly onto the radiating fin to tighten the screws, firstly
hold down with the hands; then press and move back and forth slightly until it is in full contact
before tightening the screws. When tightening the screws, take special care on the strength of
radiator materials when using the electric screwdriver, torque screwdriver or torque wrench.
Ensure that the screws are correctly tightened to position. The tightening force varies with the
module.
4. Cautions on installation of screws on inverter module: If the tightening force is applied
extremely unbalance`d during installation of the module onto the radiator, the silicon chip
inside the module may be deformed due to the stress. And this might cause damage or degrade
to the module. Therefore, be sure to operate according to the required tightening sequence.
The recommended tightening sequence for the inverter module fixed by two screws is as shown