Design Goals

Eventually the ReactorForge project may result in multiple hardware designs, but the initial goal is to build a single induction heater usable by the most people in the capacity range most common. Also be extremely rugged, reliable, user friendly and open source.

This is a list of the initial design goals for the base unit (ReactorForge - CriticalMass). All features listed here are operational in the beta unit

• Operate on 240V 34A single phase power.
• Able to operate at 100% duty cycle and at least 200% rated current.
• Easily heat a large range of material up at least 3-4".
• Easily interchange working coils.
• No manual tuning required, regardless of working coil or work piece (within reasonable limits). Automatically detect and warn user if coil dimensions cause operation outside of the frequency range.
• Inverter frequency range of 1-120KHz.
• Tank design tuned to the 25-90KHz range.
• Remote foot switch.
• Single front panel start/stop button (illuminated to indication operation).
• Audible indicator (buzzer) to indicate operation with customizable frequency, volume and period (time between beeps).
• 5 front panel soft buttons (firmware programable) and 1 rotary encoder for user input.
• 20 x 4 line backlit LCD for data display and user interface.
• Simple user interface with powerful options (the basic use should be no more complex than pushing one button but should have an intuitive underlying menu driven system that allows powerful customization).
• Current limiting functionality to limit both mains current draw and working power (inverter current).
• Thermal protection/shutdown (sensors for incoming and outgoing water, inverter cooling plate and ambient air).
• All digital operation (No limited analog PLL tuning for the inverter, no analog user I/O)
• Solid state switch output able to handle a 10A load to control a pump or valve. Prevents constant water flow when not needed.
• Low voltage power supplied by readily available ATX computer power supply.
• 100% water cooled, including internal enclosure ambient air.
• Fully enclosed/sealed case to prevent build up of shop metal dust and other nasty contaminates that will reduce the life of the machine. This requires internal cooling of the air as the water blocks and bus cooling will not be sufficient to cool the air for the components not on a water cooled surface (ie. power supply, igbt drivers and the main control board).
• Under and over voltage detection.
• IGBT drivers with over current/voltage protection to prevent IGBT module failure.
• Mains power line filter.

Features considered but not yet implemented.

• Input to allow temperature control of the work piece.
• Low voltage output to indicate unit operation.