Hitachi CL28WF720AN, C36WF810N, CL32WF720AN, CL32WF720AND, CL32WF727N Service Manual

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December 1999

SM 00025

C28WF523N

C32WF523N C32WF720N C32WF727N C32WF810N C36WF810N C36WF830N CL28WF720AN CL32WF720AN CL32WF720AND CL32WF727N CL32WF810AN CL36WF810AN CL36WF830AN D36WF840N

SERVICE MANUAL

MANUEL D’ENTRETIEN WARTUNGSHANDBUCH

CAUTION:

Before servicing this chassis, it is important that the service technician

read the “Safety Precautions” and “Product Safety Notices” in this

service manual.

ATTENTION:

ant d’effectuer l’entretien du châassis, le technicien doit lire les

«Précautions de sécurité» et les «Notices de sécurité du produit

présentés dans le présent manuel.

VORSICHT:

Vor Öffnen des Gehäuses hat der Service-

Ingenieur die

„Sicherheitshinweise“ und „Hinweise zur Produktsicherheit “ in diese

Wartungshandbuch zu lesen.

Data contained within this

Service manual is subject to

alteration for improvement.

Les données fournies dans le

présent manuel d’entretien

peuvent faire l’objet de

modifications en vue de

perfectionner le produit.

Die in diesem

War

tungshandbuch enthaltenen

Spezifikationen kö

nnen sich

zwecks Verbesserungen ändern.

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ENGLISH

SAFETY PRECAUTIONS

WARNING: The following precautions must be observed.

ALL PRODUCTS

Before any service is performed on the chassis an isolation transformer should be inserted between the power line and the product.

1. When replacing the chassis in the cabinet, ensure all the protective devices are put back in place.

2. When service is required, observe the original lead dressing. Extra precaution should be taken to ensure correct lead dressing in any high voltage circuitry area.

3. Many electrical and mechanical parts in HITACHI products have special safety related characteristics. These characteristics are often not evident from visual inspection, nor can the protection afforded by them necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified by marking with a

! on the schematics and the replacement parts list. The use of a substitute replacement component that does not have the same safety characteristics as the HITACHI recommended replacement one, shown in the parts list, may create electrical shock, fire, X-radiation, or other hazards.

4. Always replace original spacers and maintain lead lengths. Furthermore, where a short circuit has occurred, replace those components that indicate evidence of overheating.

5. Insulation resistance should not be less than 2M ohms at 500V DC between the main poles and any accessible metal parts.

6. No flashover or breakdown should occur during the dielectric strength test, applying 3kV AC or

4.25kV DC for two seconds between the main poles and accessible metal parts.

7. Before returning a serviced product to the customer, the service technician must thoroughly test the unit to be certain that it is completely safe to operate without danger of electrical shock. The service technician must make sure that no protective device built into the instrument by the manufacturer has become defective, or inadvertently damaged during servicing.

CE MARK

1. HITACHI products may contain the CE mark on the rating plate indicating that the product contains parts that have been specifically approved to provide electromagnetic compatibility to designated levels.

2. When replacing any part in this product, please use only the correct part itemised in the parts list to ensure this standard is maintained, and take care to replace lead dressing to its original state, as this can have a bearing on the electromagnetic radiation/immunity.

PICTURE TUBE

1. The line output stage can develop voltages in excess of 25kV; if the E.H.T. cap is required to be removed, discharge the anode to chassis via a high value resistor, prior to its removal from the picture tube.

2. High voltage should always be kept at the rated value of the chassis and no higher. Operating at higher voltages may cause a failure of the picture tube or high voltage supply, and also, under certain circumstances could produce X-radiation levels moderately in excess of design levels. The high voltage must not, under any circumstances, exceed 29kV on the chassis (except for projection Televisions).

3. The primary source of X-radiation in the product is the picture tube. The picture tube utilised for the above mentioned function in this chassis is specially constructed to limit X-radiation. For continued X-radiation protection, replace tube with the same type as the original HITACHI approved type

4. Keep the picture tube away from the body while handling. Do not install, remove, or handle the picture tube in any manner unless shatterproof goggles are worn. People not so equipped should be kept away while picture tubes are handled

LASERS

If the product contains a laser avoid direct exposure to the beam when the cover is open or when interlocks are defeated or have failed.

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