Iiyama Vision Master 405, Руководство по обслуживанию

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SAFETY PRECAUTION
1. The design of this product contains special hardware, many circuits and components specially for safety purposes.
For continued protection, no changes should be made to the original design unless authorized in writing by the
manufacturer. Replacement parts must be identical to those used in the original circuits. Service should be
performed by qualified personnel only.
i
Alterations of the design or circuitry of the products should not be made. Any design alterations or additions will
void the manufacturer's warranty and will further relieve the manufacturer of responsibility for personal injury or
property damage resulting therefrom.
2.
3. Many electrical and mechanical parts in the 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 in the parts list of Service manual. Electrical components
having such features are identified by mark “ ! ” on the schematics and ! on the parts list in Service manual. The
use of a substitute replacement which does not have the same safety characteristics as the recommended
replacement part shown in the parts list of Service manual may create shock, fire, or other hazards.
Use isolation transformer.
The chassis and any sub-chassis contained in some products are connected to the primary circuit of the AC
power line. An isolation transformer of adequate capacity should be inserted between the product and the AC
power supply point while performing any service on some products when the primary circuit of the AC power
supply is exposed. 4.
The high voltage applied to the picture tube must conform with that specified in Service manual. Excessive high
voltage conditions should be kept to a minimum, or should be prevented. If severe arcing occurs, remove the AC
power immediately and determine the cause by visual inspection (incorrect installation, cracked or melted high
voltage harness, poor soldering, etc.) To maintain the proper minimum level of soft X-ray emission, components
in the high voltage circuitry including the picture tube must be the exact replacements or alternatives approved
by the manufacturer of the complete product. 5.
Isolation Check
(Safety for Electrical Shock Hazard)
After reassembling the product always perform an isolation check on the exposed metal parts of the cabinet
(video input and output terminals, control knobs, screwheads, control shafts, etc.) to be sure the product is safe
to operate without danger of electrical shock.
6.
Dielectric Strength Test
The isolation between the AC primary circuit and all metal parts exposed to the user, particularly any exposed
metal part having a return path to the chassis should withstand a voltage of 1,500V AC(r.m.s.), 20mA(current
sensitivity) for a period of one minute.
This method of test requires a test equipment not generally found in the service trade.
(1)
Leakage Current Check
Plug the AC line cord directly into the AC outlet (do not use a line isolation transformer during this check.).
Using a “Leakage Current Tester”, measure the leakage current from each exposed metal part of the cabinet,
particularly any exposed metal part having a return path to the chassis, to a known good earth ground (water
pipe etc.). Any leakage current must not exceed 3.5mA AC(r.m.s.).
(2)