Safety Instructions, Warnings, and Notes
EN 4
SHA2.0U LA
2.
2.
Safety Instructions, Warnings, and Notes
2.1
Safety Instructions
Safety regulations require that
during
a repair:
Connect the set to the AC Power via an isolation
transformer (> 800 VA).
Replace safety components, indicated by the symbol
,
only by components identical to the original ones. Any
other component substitution (other than original type) may
increase risk of fire or electrical shock hazard.
Safety regulations require that
after
a repair, the set must be
returned in its original condition. Pay in particular attention to
the following points:
Route the wire trees correctly and fix them with the
mounted cable clamps.
Check the insulation of the AC Power lead for external
damage.
Check the strain relief of the AC Power cord for proper
function.
Check the electrical DC resistance between the AC Power
plug and the secondary side (only for sets which have a AC
Power isolated power supply):
1.
Unplug the AC Power cord and connect a wire
between the two pins of the AC Power plug.
2.
Set the AC Power switch to the "on" position (keep the
AC Power cord unplugged!).
3.
Measure the resistance value between the pins of the
AC Power plug and the metal shielding of the tuner or
the aerial connection on the set. The reading should be
between 4.5 Mohm and 12 Mohm.
4.
Switch "off" the set, and remove the wire between the
two pins of the AC Power plug.
Check the cabinet for defects, to avoid touching of any
inner parts by the customer.
2.2
Warnings
All ICs and many other semiconductors are susceptible to
electrostatic discharges (ESD
). Careless handling
during repair can reduce life drastically. Make sure that,
during repair, you are connected with the same potential as
the mass of the set by a wristband with resistance. Keep
components and tools also at thissame potential. Available
ESD protection equipment:
–
Complete kit ESD3 (small tablemat, wristband,
connection box, extension cable and earth cable) 4822
310 10671.
–
Wristband tester 4822 344 13999.
Be careful during measurements in the high voltage
section.
Never replace modules or other components while the unit
is switched "on".
When you align the set, use plastic rather than metal tools.
This will prevent any short circuits and the danger of a
circuit becoming unstable.
2.3
Notes
2.3.1
Lead Free Solder
Philips CE is going to produce lead-free sets (PBF) from
1.1.2005 onwards.
Lead-free sets will be indicated by the PHILIPS-lead-free logo
on the Printed Wiring Boards (PWB):
This sign normally has a diameter of 6 mm, but if there is less
space on a board also 3 mm is possible.
Always use the highest temperature to solder, when using
SAC305 (see also instructions below).
indicates 2.2 kohm).
De-solder thoroughly (clean solder joints to avoid mix of
two alloys).
Caution:
For BGA-ICs, you
must
use the correct temperature-
profile, which is coupled to the 12NC. For an overview of these
profiles, visit the website
www.atyourservice.ce.philips.com
(needs subscription, but is not available for all regions)
You will find this and more technical information within the
"Magazine", chapter "Workshop information".
For additional questions please contact your local repair-
helpdesk.
Due to lead-free technology some rules have to be respected
by the workshop during a repair:
Use only lead-free soldering tin Philips SAC305 with order
code 0622 149 00106. 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 adquate solder tools applicable for lead-free
Figure 2-1 Lead-free logo
Pb
In case of doubt wether the board is lead-free or not (or with
mixed technlogies), you can use the following method:
sodering tin. The solder tool must be able
–
To reach at least a solder-tip temperature of 400˚C.
To stabilise the adjusted temperature at the solder-tip.
–
–
To exchange solder-tips for different applications.
Adjust your solder tool so that a temperature around 360˚C
- 380˚C is reached and stabilised 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 rise 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 PHILPS recommends strongly to
avoid mixed regimes. If not to avoid, clean carefully the
solder-joint from old tin and re-solder with new tin.
Use only original spare-parts listed in the Service-Manuals.
Not listed standard material (commodities) has to be
purchased at external companies.
Special information for lead-free BGA ICs: these ICs will be
delivered in so-called "dry-packaging" to protect the IC
against moisture. This packaging may only be opened
short before it is used (soldered). Otherwise the body of the
IC gets "wet" inside and during the heating time the
structure of the IC will be destroyed due to high (steam-
)pressure inside the body. If the packaging was opened
before usage, the IC has to be heated up for some hours
(around 90˚C) for drying (think of ESD-protection !).
Do not re-use BGAs at all
!
For sets produced before 1.1.2005, containing leaded
soldering tin and components, all needed spare parts will
be available till the end of the service period. For the repair
of such sets nothing changes.
