Panasonic inverter NN-CT880MBPQ, Service Manual

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NN-CT880MBPQ NN-CT870WBPQ
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10.3. Digital Programmer Circuit
(DPC) and membrane key
board.
NOTE: Ground any static electric built up on your body before
handling the DPC.
1. Disconnect all connectors from the DPC.
2. Remove the four screws holding the escutcheon base
and slide the escutcheon base upward slightly. removal is
easier with the door open.
3. Release the flat cable.
4. Remove the five screws holding the DPC HU assembly
5. Remove the door lever
6. Remove the eight screws holding the DPC AU assembly
To remove escutcheon pad
1. Remove the escutcheon bracket from the escutcheon
base by freeing the 4 catch hooks on the escutcheon
base.
2. Peel away the display window from the inside of the base.
3. Remove the membrane assembly by pushing from the
inside of the base and then peeling away from the outside
surface.
NOTE:
1. The escutcheon key board is attached to the escutcheon
base with double faced adhesive tape. Therefore, apply-
ing hot air such as using a hair dryer is recommended for
smoother removal
2. When installing a new escutcheon key board, make sure
that the surface of the escutcheon base is cleared suffi-
ciently so that problems such as, shorted contacts and
uneven surfaces can be avoided.
10.4. Low voltage transformer and/
or power relays
Note
Be sure to ground your body to discharge any static
before handling the DPC.
1. Using a solder wick or a de soldering tool and a 30W sol-
dering iron, carefully remove all solder from the terminal
pins of the low voltage transformer and/or power relays.
2. With all of the terminal pins cleaned and separated from
the DPC contacts, remove the defective transformer/
power relays and install the new components making
sure that the terminal pins are inserted completely. Care-
fully re solder all terminal contacts carefully.
Note
Do not use a soldering iron or de soldering tool of more
than 30 watts on DPC contacts
Removal of DPC AU and DPC HU
Figure 5
Disconnecting the PCB lock connector
Figure 4