Sharp LC-24LE240E Service Manual page 5

LC-24LE240
PRECAUTIONS FOR USING LEAD-FREE SOLDER
1 Using lead-free wire solder
When fi xing the PWB soldered with the lead-free solder, apply lead-free wire solder. Repairing with conventional lead wire solder
may cause damage or accident due to cracks.
As the melting point of lead-free solder (Sn-Ag-Cu) is higher than the lead wire solder by 40°C, we recommend you to use a
dedicated soldering bit, if you are not familiar with how to obtain lead-free wire solder or soldering bit, contact our service station
or service branch in your area.
2 Soldering
As the melting point of lead-free solder (Sn-Ag-Cu) is about 220°C which is higher than the conventional lead solder by 40°C,
and as it has poor solder wettability, you may be apt to keep the soldering bit in contact with the PWB for extended period of time.
However, Since the land may be peeled off or the maximum heat-resistance temperature of parts may be exceeded, remove the
bit from the PWB as soon as you confi rm the steady soldering condition.
Lead-free solder contains more tin, and the end of the soldering bit may be easily corroded. Make sure to turn on and off the
power of the bit as required.
If a different type of solder stays on the tip of the soldering bit, it is alloyed with lead-free solder. Clean the bit after every use of it.
When the tip of the soldering bit is blackened during use, fi le it with steel wool or fi ne sandpaper.
Be careful when replacing parts with polarity indication on the PWB silk.
Lead-free wire solder for servicing.
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