IEEE Std 1653.1 pdf download IEEE Standard for Traction Power Rectifer Transformers for Substation Applications up to 1500 V DC Nominal Output cast-coil or cast-resin rectifier transformers: A transformer with windings that are vacuum cast or vacuumimpregnated in epoxy resin and fillers, and cured under a vacuum for purpose of minimizing the probability ofair voids contributing to partial discharges at...