What is it?

A reflow oven controller (ROC) for reflow soldering of surface mount components using a mini/toaster oven.

Tell me more.

The ROC is a PID temperature controller with set point ramping for use with a k-type thermocouple and has a maximum temperature setting of 260 degrees Celsius.

Android application can run on all devices with Bluetooth Low Energy aka Bluetooth Smart which is available on Android from version 4.3 and up. If the ‘app’ installs you have it.

A profile editor, with 5 custom profiles, is easy to learn and use. Adjustment is either by gesture or keyboard input. Each segment can be adjusted and viewed in real time on all screen resolutions. All profile data is stored on the ROC so all devices will have access to the same data. The editor keeps a record of adjusted data if you forget to save so you won’t have to do it all over again. Simply return to edit view and double tap graph.

ROC has reverse polarity protection and can supply the SSR from 3v3 or Vin (4 - 15Vdc). DC supply can be battery or low-ripple unregulated DC. After shutdown the ROC regulator draws less than 1 uA. A low battery warning will be displayed when the batteries have given most of their useful energy. I recommend 4AA or 4AAA alkaline batteries.

Board dimensions are 40 x 50 mm. Connection pitch is 0.1” so you can use pin headers, PCB screw terminal or solder wiring directly to board.

Easy operation: tap the ‘app’ icon and push the start button to start the ROC advertising.

Why did you make it?

My previous reflow oven controller used the PC to graph time/temperature data, while this worked very well it was inconvenient. Now I have the display and control in my hand.

What if the Bluetooth connection is lost?

The ROC is fully autonomous, should you drop your device in a bucket of water or put it in the microwave oven or it takes a hit from a sniper, fear not as the ROC will carry on and run the profile until the end.

What do I get and what do I need to complete it?

You get the tested and calibrated ROC controller board. You will need the following to complete the project:

• Momentary push-button.
• Zero-crossing solid state relay of adequate Ampere rating for your chosen oven Wattage and regional Voltage.
• Fast response K-type thermocouple rated above the ROC max temperature of 260C.
• Box, which can be a combination of metal and plastic as per your Android device, but not all metal.
• Mini/toaster oven. 1000 Watt - 1800 Watt. All things considered, a 1300 Watt is ideal if its volume is small, say less than 20 litres. A 6 Amp SSR (Europe) or 12 Amp SSR (North America) would cover it.

What makes it special?

• No oven modifications necessary.
• No PC required.
• Free Android 'app' on Google Play.
• Profile editor.