The profile graph will tell you whether or not your process is within spec and that your reflow oven is creating the correct profile, nothing more. Double check your set-up again before diving into your profile. The information from the graph must be “true.”
There are dozens of software packages that mostly render the same information, with temperature on the Y axis and time across oven zones on the X axis. These software packages vary great with respect to how they manipulate this data or allow you to play around with the numbers.
Not all of your oven set points are going to match those of your profiling software. Profiling software can do this automatically but not all oven brands communicate with all profiling software brands. In the end, you might be left with a graph that appears to be in spec but, in reality, is meaningless due to differences in the set points in the oven and in the profiling software.
To be considered relevant, ALL profiles must follow these guidelines:
- Profiles are generated by a specification from the solder paste manufacturer, component suppliers and substrate tolerances.
- The set points of the oven heating zones are set.
- The oven conveyor speed is set.
- The profiler set points are the same as the oven heating zone set points.
- The profiler oven conveyor speed is the same as the oven.
- The reported number of heating zones are the same as the number of oven heating zones.
- Any change in the set points of the oven MUST be changed to the profiler software.
Any violation of these guidelines will render your profile invalid and meaningless!
