With the extensive use of BGA, CSP and 0201 components, especially the use of lead-free solders, the importance of high-precision control of reflow oven temperatures is increasingly recognized by people.
The reflow soldering real-time control system, like a camera, can monitor the reflow oven for 24 hours, track each PCBA electronic product in the process, and record the furnace temperature. It ensures that the best craft capability is maintained, identifies problems before potential defects occur, and provides detailed, objective data to the craft personnel at all times.
The schematic diagram of the reflow soldering real-time monitoring system is shown in Figure 1. For the same product, only one temperature curve is need to be measured. As a reference curve, the monitoring system monitors the temperature changes at different positions of the furnace chamber through the thermocouples in the temperature detecting tubes on both sides of the track, thereby estimating the real-time temperature of each test point on the PCB. Using the reference curve as a standard, an accurate simulation curve is inferred for each PCB in the process. The simulation temperature curve can be retained for a long time. When the SMD welding quality at a certain moment is suspected, the simulated temperature curve in the furnace can be called up by inputting the processing time, and the abnormality of the furnace temperature can be detected at a glance.
The above are the powerful benefits of real-time monitoring systems in reflow soldering equipment, and many PCB quality controls also need to rely on this.