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high temperature solder such as silver / tin alloy, and the solder joint should be as
small as possible.
Another acceptable method is fast, easy, and accurate enough for most applications.
A small amount of thermal compound (also known as thermal paste or grease,
which is often used on computer CPU or graphics card CPU) spots cover the
thermocouple, and then stick it with high-temperature tape (such as Kapton).
Another way to attach thermocouple is to use high-temperature adhesives, such as
cyanoacrylate adhesives. This method is usually not as reliable as other methods.
The attachment position should also be selected. It is usually better to attach the
thermocouple tip between the PCB pad and the corresponding component pin or
metal end.
(Figure 1. Attach thermocouple tip between PCB pad and corresponding
component pin or metal end)
The table of solder paste characteristic parameters is also necessary, and the
information contained in it is very important to the temperature wave, such as the
desired duration of temperature wave, the active temperature of solder paste, the
melting point of alloy and the desired maximum temperature of reflow.
Before you start, you must have a basic understanding of the ideal temperature
wave. Theoretically, the ideal wave consists of four parts or sections, the first three
regions are heated and the last one is cooled. The more the temperature zone of the
oven, the more accurate and close the profile of the temperature wave can be
achieved. Most pastes can be successfully reflowed with four basic temperature
zones.