Abstract: A method measures three line-to-line voltages and constructs a phasor triangle with the voltages phasors. Vab extends from a first point horizontally to the origin. Vbc extends between the origin and a second point. Vca extends between the second point and the first point. The method includes adding a first line segment that extends from a point that bisects Vbc in a direction perpendicular to Vbc to a third point. The method adds a second line segment from a point that bisects Vca in a direction perpendicular to Vca to a fourth point. The method adds a third line segment from the third point to the first point and a fourth line segment from the fourth point to the origin. The third line segment intersects the fourth line segment at a neutral point. A line-to-neutral voltage is a line from the neutral point to a vertex of the phasor triangle.

Abstract: Methods and systems for communicating information from a first modular electronic device to a second modular electronic device. The first modular electronic device transmitting a first serial data frame over a two-wire communication protocol. The first serial data frame containing status information, a heartbeat challenge and a frame check character. The second modular electronic device able to receive the first serial data frame, validate the data and display status information on a local human interface. The second electronic device able to respond to the first electronic device by transmitting a second serial data frame. The second serial data frame containing a heartbeat response and a frame check character response. The first modular electronic device having the ability to place a modular electronic overload system in a safe state if communication is lost between the first modular electronic device and the second modular electronic device.