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Reflow Profile:-
The reflow temperature profile is defined by the relationship of temperature versus time during heating. Thermal profile use to monitor wave soldering, reflow soldering, selective soldering.
Reflow Zones:- Reflow Zones divided into four sections.
Pre-Heating Zone.
Soak Zone.
Peak Zone / Reflow Zone.
Cooling Zone.
Two types of profiling process.
Continuous Real time profiler.
Offline profiler.
Thermocouple:-
What is thermocouple :- A Thermocouple is a sensor used to measure temperature. Thermocouples consist of two wire legs made from different metals. The wires legs are welded together at one end, creating a junction. This junction is where the temperature is measured.
How to work:- When the junction experiences a change in temperature, a voltage is created. The voltage can then be interpreted using thermocouple reference tables to calculate the temperature.
Profiler / Device:- Profiler comes with the different channels.
ECD
Fluke, Datapaq
KIC
Profile Types:- There are two basic temperature profile types.
Ramp-Soak-Spike (RSS).
Ramp-to-Spike (RTS).
The RTS temperature profiles are suitable for use in most applications for enhanced solder performance.
The most things to control in profiling is:-
1. Zone set point temperature.
2. Conveyor Speed.
3. Convection rate.
Three basic controls:-
1. Zone Temperature- Controls the profile slop in that zone.
*Higher temperature increase heating range.
*Lower temperature reduces heating range.
2. Conveyor Speed:- Controls the time spend in all zones.
*Slow speed increase the time in all zones.
*Faster speed decrease the time in all zones.
3. Convections Rate- Control the flow of heat in all zone.
*Higher rate increase heating rate at the same temp set points.
*Lower rate decrease heating rate at the same temp set points.
*Higher rate reduce temp difference between components.
What’s need to Profile:-
Product to profile
Thermocouples
Profiler
Thermal Protective Barrier
Carrier for Profile
T/C attachment solder and tapes.
Soldering iron
Gloves
Cooling fan