What are the symptoms, causes and solutions to neutral-to-ground voltage events?
Neutral-to-ground voltage is any voltage measurable between the neutral conductor and the grounding conductor, usually reflecting voltage losses in the neutral conductor due to neutral return current. Neutral-to-ground voltage can affect electronic equipment if the amplitude of the voltage exceeds the withstand capability of the load. Typical symptoms of neutral-to-ground voltage events include parity errors, poor resolution, erratic equipment operation, the need to reset/reboot equipment and, for telecommunications systems, dropped calls. There are numerous causes of neutral-to-ground voltage events. Common causes are large-equipment startup, loose neutral wiring and grounding wires, loose or missing neutral-to-ground bond, excessive ground and neutral current. Solutions to neutral-to-ground voltage problems are straightforward: correct faults to ground, repair wiring problems, add larger neutral wires, or add transformer isolation.