Sharp CD-MPS900, Service Manual

Page: 2 / 104

CD-MPS900/CD-MPS99
– i –
IMPORTANT SERVICE NOTES
BEFORE RETURNING THE AUDIO PRODUCT
BEFORE RETURNING THE AUDIO PRODUCT
(Fire & Shock Hazard)
Before returning the audio product to the user, perform the following
safety checks.
1. Inspect all lead dress to make certain that leads are not pinched or
that hardware is not lodged between the chassis and other metal
parts in the audio product.
2. Inspect all protective devices such as insulating materials, cabinet,
terminal board, adjustment and compartment covers or shields,
mechanical insulators etc.
3. To be sure that no shock hazard exists, check for leakage current in
the following manner.
* Plug the AC line cord directly into a 120 volt AC outlet.
* Using two clip leads, connect a 1.5 kohm, 10 watt resistor paralleled
by a 0.15 µF capacitor in series with all exposed metal cabinet parts
and a known earth ground, such as conduit or electrical ground con-
nected to earth ground.
* Use a VTVM or VOM with 1000 ohm per volt, or higher, sensitivity to
measure the AC voltage drop across the resistor (See diagram).
* Connect the resistor connection to all exposed metal parts having a
return path to the chassis (antenna, metal cabinet, screw heads,
knobs and control shafts, escutcheon, etc.) and measure the AC
voltage drop across the resistor.
All check must be repeated with the AC line cord plug connection
reversed.
Any reading of 0.3 volt RMS (this corresponds to 0.2 milliamp. AC.) or
more is excessive and indicates a potential shock hazard which must
be corrected before returning the audio product to the owner.
TO EXPOSED
METAL PARTS
CONNECT TO
KNOWN EARTH
GROUND
TEST PROBE
0.15 mF
1.5 kohms
10 W
VTVM
AC SCALE