Reflow Oven Fan Controller PCB

Problem

A small module from a large reflow oven which controls cooling fans was sent in for repair. The output was not operating. No datasheet or schematic was available.

Diagnosis

We determined the unit needed a 240v AC supply, it drives 12v fans and has an opto-isolated control input. Initially we found a damaged SMT push button.

The spring in the button was collapsed and shorted at all times so we removed it. We set up a way to test the unit on the bench and found it functions as expected. Shorting the switch pads recreated the same issue as reported by the customer and made a green LED light.

Solution

A replacement push button was ordered and fitted. The unit is now back in the customer's reflow oven and in regular use.

If you are experiencing similar issues and would like to discuss or request a quote, email us at This email address is being protected from spambots. You need JavaScript enabled to view it.
or call 01303 489 698.