Safety Instruction, Warnings and Notes

200VW8 LCD

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Safety instruction, warnings and notes

index of this chapter: 1 Safety Instructions 2 Warnings

3 Notes

1 Safety Instructions

Safety regulations require that during a repair:

a. Connect the set to the AC Power via an isolation transformer (> 800 VA).

b. 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:

a. Route the wire trees correctly and fix them with the mounted cable clamps.

b. Check the insulation of the AC Power lead for external damage.

c. Check the strain relief of the AC Power cord for proper function.

d. 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):

*Unplug the AC Power cord and connect a wire between the two pins of the AC Power plug.

*Set the AC Power switch to the "on" position (keep the AC Power cord unplugged!).

*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.

*Switch "off" the set, and remove the wire between the two

Pins of the AC Power plug.

e. Check the cabinet for defects, to avoid touching of any inner parts by the customer.

2 Warnings

a. 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 this same potential.

b. Be careful during measurements in the high voltage section. c. Never replace modules or other components while the unit

is switched "on".

d. 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.

3Notes 3.1 General

Measure the voltages and waveforms with regard to the chassis ground or hot ground, depending on the tested area of circuitry. The voltages and waveforms shown in the diagrams are indicative.

The semiconductors indicated in the circuit diagram and in the parts lists, are interchangeable per position with the semiconductors in the unit, irrespective of the type indication on

3.2 Schematic Notes

All resistor values are in ohms and the value multiplier is often used to indicate the decimal point location (e.g. 2K2 indicates 2.2 Kohm).

Resistor values with no multiplier may be indicated with either an "E" or an "R" (e.g. 220E or 220R indicates 220 ohm).

All capacitor values are given in micro-farads ( X10-6), nano-farads (n= X10-9), or pico-farads (p= X10-12).

Capacitor values may also use the value multiplier as the decimal point indication (e.g. 2p2 indicates 2.2 pF).

An "asterisk" (*) indicates component usage varies. Refer to the diversity tables for the correct values.

The correct component values are listed in the Electrical Replacement Parts List. Therefore, always check this list when there is any doubt.

3.3 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.

In case of doubt wether the board is lead-free or not (or with mixed technologies), you can use the following method:

*Always use the highest temperature to solder, when using SAC305 (see also instructions below).

*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 http://www.atyourservice.ce.philips.com/ You will find this and more technical information within the "Magazine", chapter "Workshop information".

For additional questions please contact your local repair desk.

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 adequate solder tools applicable for lead-free soldering tin. The solder tool must be able

-To reach at least a solder-tip temperature of 400 degree C.

-To stabilise the adjusted temperature at the solder-tip.

-To exchange solder-tips for different applications.

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Philips 200VW8FB service manual Safety Instruction, Warnings and Notes, Safety instruction, warnings and notes