Volt-Pac® Variable Transformers provide continuously adjustable voltage to an electrical load from a fixed line voltage. Operation is based on autotransformer action in unsaturated magnetic components, so the output waveform is a precise reproduction of the input waveform.
Load connections are provided for voltage ranges of 0-100% and 0-117%. When using the 117% range, rated amps must not be exceeded. Maximum amps are the current that can safely be drawn at full output on the 100% range. Maximum amps must be decreased as the output voltage is decreased until rated current is reached.
Maximum amps capability is most useful with resistive loads. Load power factor has little effect on transformer operation from 0.5 lagging to 0.5 leading. The load power factor is reflected to the line with negligible change. These Volt-Pac® transformers are available for loads to 360A or 560V. They will withstand an overload of 2.5X rated current for five minutes.