Text preview for : Precaution.pdf part of Samsung Precaution Samsung Proj TV SP-43J6HDX ch.M51A Precaution.pdf

Back to : Precaution.pdf | Home


1. Precautions
Follow these safety, servicing and ESD precautions to prevent damage and protect against potential
hazards such as electrical shock and X-rays.

1-1 Safety Precautions

1. Be sure that all of the built-in protective
devices are replaced. Restore any missing (READING SHOULD
protective shields. LEAKAGE NOT BE ABOVE
2. When reinstalling the chassis and its
assemblies, be sure to restore all protective EXPOSED METAL
devices, including: nonmetallic control knobs
and compartment covers.
3. Make sure that there are no cabinet openings (USING AC ADAPTER EARTH
through which people--particularly PLUG AS REQUIRED) GROUND

children--might insert fingers and contact
dangerous voltages. Such openings include
Fig. 1-1 AC Leakage Test
the spacing between the picture tube and the
cabinet mask, excessively wide cabinet
6. Antenna Cold Check:
ventilation slots, and improperly fitted back
With the unit's AC plug disconnected from the
AC source, connect an electrical jumper across
the two AC prongs. Connect one lead of the
If the measured resistance is less than 1.0
ohmmeter to an AC prong. Connect the other
megohm or greater than 5.2 megohms, an
lead to the coaxial connector.
abnormality exists that must be corrected
before the unit is returned to the customer.
7. X-ray Limits:
The picture tube is especially designed to pro-
4. Leakage Current Hot Check (Figure 1-1):
hibit X-ray emissions. To ensure continued
Warning: Do not use an isolation
X-ray protection, replace the picture tube only
transformer during this test. Use a leakage-
with one that is the same type as the original.
current tester or a metering system that
Carefully reinstall the picture tube shields and
complies with American National Standards
mounting hardware; these also provide X-ray
Institute (ANIS C101.1, Leakage Current for
Appliances), and Underwriters Laboratories
(UL Publication UL1410, 59.7).
8. High Voltage Limits:
High voltage must be measured each time ser-
5. With the unit completely reassembled, plug
vicing is done on the B+, horizontal deflection
the AC line cord directly into the power
or high voltage circuits. Correct operation of
outlet. With the unit's AC switch first in the
the X-ray protection circuits must be
ON position and then OFF, measure the
reconfirmed whenever they are serviced.
current between a known earth ground (metal
(X-ray protection circuits also may be called
water pipe, conduit, etc.) and all exposed
"horizontal disable" or "hold-down".)
metal parts, including: antennas, handle
brackets, metal cabinets, screwheads and
Heed the high voltage limits. These include
control shafts. The current measured should
the X