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OCTOBER 2019 I PCB007 MAGAZINE 31 This phenomenon also works in reverse. In the same way a magnetic field is created by an electric current moving in a coil, an electric current can be made to flow in the presence of a magnetic field. In other words, a magnetic field can induce electric currents in a second- ary coil if the magnetic field is placed in proper alignment to the primary coil (Figure 3). Now, if we look at what would be the elec- trical function of a simple metal plate prop- erly aligned with such a magnetic field, then that metal plate is working as one turn coil in a short circuit for the induced currents. The metal plate previously mentioned refers to the stainless-steel separator plates of the press stack (Figure 4). The InduBond X-Press Technology has been developed to convert such energy induced on each stainless-steel separator plates (induced electric energy) into thermal energy (heat) by the eddy-current loss theory [2] . The resulting magnetic field generated by the coil is propor- tional to the main coil geometry seen in Figure 2. The stack of stainless-steel plates and panels to be heated in the press can also be consid- ered as proportional to the magnetic field be- cause the stackup contains the same size and thickness of separator press plates throughout. Therefore, induced energy is proportional and uniform, generating the same amount of heat on every separator press plate of the stack. A temperature sensor introduced into a dum- my panel in the center of the press stack pro- vides real-time feedback of the temperature of the material. A closed-loop regulating control system uses real-time information provided by the temperature sensor (in concert with other feedback systems of the press) to constantly up- date the temperature, vacuum, pressure, and power control algorithms. A heating profile can now be programmed on a computer for the con- trol algorithms to track the desired power deliv- ered to the press stack to maintain or control the temperature as desired in real time (Figure 5). The New Concept of Heat Transfer This InduBond technology does not heat the big mass of the platens; the platens in this tech- nology are cold and truly thermally isolated from the machine's heavy structure. The mag- Figure 3: Secondary electric coil aligned to the primary coil. Figure 5: Close-loop control regulation system diagram. Figure 4: Press stack separator press plates as the secondary coil.