Reflow soldering - Part (2) Measuring temperature

Thermocouple and serial data connections
MAX6675 on underside of top board

Temperature in my electronics lab

Since posting Part (1) on 8 October I can now measure temperature with 0.25C resolution using the MAX6675 temperature sensor chip and a thermocouple. I wrote some code for a PIC microcontroller's MSSPI to receive the 16 bits of serial temperature data from the MAX6675, display a value and update it every second. The display also shows the phase in progress during the reflow-soldering process, e.g., ramp to soak.

The next step of this project is to use the temperature measurement as the basis for controlling the rate of temperature change inside the oven. I have the plots made earlier of the temperature change at various power duty-cycles to the elements and I shall be using these at the starting point for each phase of the process