Marantz LC3050, Service Manual

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SERVICE MANUAL
PAGE:2
SAFETY PRECAUTIONS
Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor between a known good earth
ground (Water Pipe, Conduit, etc.) and the exposed metallic parts.
Measure the AC voltage across the resistor using AC voltmeter with 1000 ohms/volt or more
sensitivity.
Reverse plug of the AC cord into the AC outlet and repeat AC voltage measurements for each
exposed metallic part. Any voltage measured must not exceed 0.75 volt RMS, which is,
corresponds to 0.5mA.
In case any measurement is out of the limits specified, there is possibility of shock hazard and
the set must be checked and repaired before it is returned to the customer.
Leakage Current Hot Check circuit
!! Import ant Safety Notice !!
Many electrical and mechanical parts in this chassis have special safety-related
characteristics.
These parts are identified by in the Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components
as recommended in this manual to prevent Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.