Articles about low voltage problem
How Single Phase Voltage Regulators Work to Correct Abnormal Voltage Conditions: Single Phase Servo Voltage Regulators determine automatically the change in voltage as the constant voltage. This is accomplished by using electro-mechanic, passive or active components. The Servo Voltage Regulator makes the comparison between the real output voltage and the inner reference voltages.
Ed in Kansas asks; Why is there only 48volts between the neutral and ground on an electric outlet? How to Identify the Cause of a Low Voltage Condition of an Outlet.
Why is the electrical circuit voltage not reading normal with a voltage tester? How to Locate a Voltage Problem, Electrical Tests for Locating the Cause of Incorrect Voltage.