Philips 50PUT7303/79, Руководство по обслуживанию

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IC Data Sheet information section in this manual.
2.3.5 Lead-free Soldering
Due to lead-free technology some rules have to be
respected by the workshop during a repair:
•
Use only lead-free soldering tin. If lead-free solder paste
is required, please contact the manufacturer of your
soldering equipment. In general, use of solder paste
within workshops should be avoided because paste is
not easy to store and to handle.
•
Use only adequate solder tools applicable for lead-free
soldering tin. The solder tool must be able:
–
To reach a solder-tip temperature of at least 400°C.
–
To stabilize the adjusted temperature at the solder-tip.
–
To exchange solder-tips for different applications.
•
Adjust your solder tool so that a temperature of around
360°C - 380°C is reached and stabilized at the solder
joint. Heating time of the solder-joint should not exceed ~
4 sec. Avoid temperatures above 400°C, otherwise
wear-out of tips will increase drastically and flux-fluid will
be destroyed. To avoid wear-out of tips, switch “off”
unused equipment or reduce heat.
•
Mix of lead-free soldering tin/parts with leaded soldering
tin/parts is possible but PHILIPS recommends strongly to
avoid mixed regimes. If this cannot be avoided, carefully
clear the solder-joint from old tin and re-solder with new
tin.
2.3.6 Alternative BOM identification
It should be noted that on the European Service website,
“Alternative BOM” is referred to as “Design variant”.
The third digit in the serial number (example:
AG2B0335000001) indicates the number of the alternative
B.O.M. (Bill Of Materials) that has been used for producing
the specific TV set. In general, it is possible that the same
TV model on the market is produced with e.g. two different
types of displays, coming from two different suppliers. This
will then result in sets which have the same CTN
(Commercial Type Number; e.g. 28PW9515/12) but which
have a different B.O.M. number.
By looking at the third digit of the serial number, one can
identify which B.O.M. is used for the TV set he is working
with. If the third digit of the serial number contains the
number “1” (example: AG1B033500001), then the TV set
has been manufactured according to B.O.M. number 1. If
the third digit is a “2” (example: AG2B0335000001), then
the set has been produced according to B.O.M. no. 2. This
is important for ordering the correct spare parts!
For the third digit, the numbers 1...9 and the characters
A...Z can be used, so in total: 9 plus 26= 35 different
B.O.M.s can be indicated by the third digit of the serial
number.
Identification: The bottom line of a type plate gives a
14-digit serial number. Digits 1 and 2 refer to the production
centre (e.g. SN is Lysomice, RJ is Kobierzyce), digit 3 refers
to the B.O.M. code, digit 4 refers to the Service version
change code, digits 5 and 6 refer to the production year,
and digits 7 and 8 refer to production week (in example
below it is 2010 week 10 / 2010 week 17). The 6 last digits
contain the serial number.
Figure 3-1 Serial number (example)
2.3.7 Board Level Repair (BLR) or Component Level
Repair (CLR)
If a board is defective, consult your repair procedure to
decide if the board has to be exchanged or if it should be
repaired on component level.
If your repair procedure says the board should be
exchanged completely, do not solder on the defective board.
Otherwise, it cannot be returned to the O.E.M. supplier for
back charging!
2.3.8 Practical Service Precautions
•
It makes sense to avoid exposure to electrical shock.
While some sources are expected to have a possible
dangerous impact, others of quite high potential are of
limited current and are sometimes held in less regard.