Low Voltage Transformer And/Or Power Relays (Ry1) (Nn-St340M/W) - Panasonic NN-ST340M Service Manual

5. Separate D.P.C board from tabs on the escutcheon base
and remove D.P.C board.
To replace membrane key board
6. Remove 1 screw holding back plate and bracket on
escutcheon base, then remove back plate and bracket.
7. Use tools such as kinfe etc. to lift the edge of membrane
sheet and peel off escutcheon sheet & key board
membrane completely from escutcheon base.
NOTE:
a. The membrane key board is attached to the
escutcheon base with double faced adhesive tape.
Therefore, applying hot air such as using a hair dryer
is recommended for smoother removal.
b. When installing the new key board membrane, make
sure that the surface of escutcheon base is clean to
prevent a malfunction or shorted contacts.
NN-ST340M / NN-ST340W / NN-SM330M / NN-SM330W / NN-SM320M
6.3. Low voltage transformer
and/or power relays (RY1)
(NN-ST340M/W)
NOTE:
Be sure to ground any static electric charge built up on
your body before handling the D.P.C.
1. Disconnect all connectors from D.P.C. board.
2. Remove 5 screws holding D.P.C. board on escutcheon
base.
3. Replace D.P.C. board.
(A) Using solder wick or a desoldering tool and 30W
soldering iron carefully remove all solder from the terminal
pins of the low voltage transformer and/or power relays.
NOTE:
Do not use a soldering iron or desoldering tool of
more than 30 watts on D.P.C. contacts.
(B) With all the terminal pins cleaned and separated from
D.P.C. contacts, remove the defective transformer/power
relays, Replace components making sure all terminal pins
are inserted completely resolder all terminal contacts
carefully.
11