Glowing connections in DC circuits

Abstract

Measurements have been conducted to show that glowing connections can occur in DC circuits at voltages as low as 12Vdc. Properties of glowing connections for dc circuit conditions for a variety of electrically conductive materials is presented. Results reveal glowing connection characteristics for commonly used conductor material found in electrical circuits (copper and steel) for 12V, 24V, and 48V DC circuits up to 10A. It was found that material type has a pronounced effect on the glowing voltage, with copper oxides having a negative temperature coefficient (NTC) of resistance and iron oxides having a flat (zero temperature coefficient-ZTC) to slight positive temperature coefficient (PTC) of resistance. There is also a discussion on the influence of oxide resistivity, circuit polarity, and circuit conditions on DC glowing connection properties.