Haier NS-F27C, Руководство по обслуживанию

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CAUTION: Be sure no power is applied to the chassis or circuit, and observe all
Warning and Cautions
other safety precautions.
8. Minimize bodily motions when handling unpackaged replacement ES devices.
(Otherwise even some normally harmless motions such as mutual brushing of your
clothes’ fabric or lifting of your foot from a carpeted floor might generate static
electricity sufficient to damage an ES device.)
General Soldering Guidelines
1. Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape
that will maintain tip temperature within the range of 500
o
f to 600
o
f.
2. Use an appropriate gauge of RMA resin-core solder composed of 60 parts tin/40
parts lead.
3. Keep the soldering iron tip clean and well tinned.
4. Thoroughly clean the surfaces to be soldered. Use a mall wire bristle (0.5 inch, or
1.25cm) brush with a metal handle. Do not use freon-propelled spay-on cleaners.
5. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.(500
o
F to 600
o
F)
b. Heating the component lead until the solder melts.
c. Quickly draw the melted solder with an anti-static, suction-type solder removal
device with solder braid.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
6. Use the following unsoldering technique
a. Allow the soldering iron tip to reach normal temperature.(500
o
F to 600
o
F )
b. First, hold the soldering iron tip and solder the strand against the component
lead until the solder melts.
c. Quickly move the soldering iron tip to the junction of the component lead and
the printed circuit foil, and hold it there only until the solder flows onto and
around both the component lead and the foil.
CAUTION: Work quickly to avoid overheating the circuit board printed foil.
d. Closely inspect the solder area and remove any excess or splashed solder
with a small wire-bristle brush.
Remove /Replacement
Some chassis circuit boards have slotted holes (oblong) through which the IC leads are
inserted and then bent flat against the circuit foil. When holes are of slotted type, the
following technique should be used to remove and replace the IC. When working with
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