LM317T Voltage Regulator with Pass Transistor

Ferroresonant UPSThe majority of pulse power units have a serious disadvantage. There is a power supply break when the unit is switched into battery operation and back. The break occurs because mechanical switches are used. Their actuation time is only several milliseconds but still it is different from zero. It would be nice if a UPS had some smart gadget inside for maintaining load voltage while the switch is actuated. Such gadget was actually invented in the US in 1938 by Joseph Solo. It is called a ferroresonant transformer.To a certain extent, a ferroresonant UPS is a variety of uninterruptible power supplies which interact with the main. However, there is component introduced into this UPS circuit which changes its operation drastically. This is a ferroresonant transformer. It is connected into a ferroresonant UPS circuit instead of the autoconnected transformer with taps in the UPS circuit which interacts with the main. So, its functions are as follows. It stabilizes voltage across the UPS output. This allows operating in a wide range of supply voltages without switching into battery operation. There is also no switching inside the UPS itself. A ferroresonant transformer controls voltage and does not require taps switching. A ferroresonant transformer has a considerable inductance. A great amount of energy accumulates in the transformer's magnetic field during the UPS operation from the main. When power supply stops the transformer supplies the energy which has ...



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