Abstract: A system and method for coordinating shunt reactance switching in a system with a transformer having a primary voltage and a secondary voltage for supplying low voltage power to a load. Voltage and power meters are provided for measuring the primary voltage and the reactive power flowing to the load. A programmable logic controller receives as one set of inputs measurements of primary voltage and reactive power flowing to the load, and as another set of inputs, predetermined ranges establishing high and low limits for the primary voltage and the reactive power. Based on these inputs, the programmable logic controller connects or disconnects at least one shunt reactance to maintain the load voltage substantially constant.