Short Circuits on Low Voltage D.C. Distribution Facilities

This paper concerns the effect of short circuits on low voltage, dc distribution systems. Such short circuits cause high voltage transients but little is known about the magnitude and duration of these transients. The authors have analyzed some typical circuits and determined the controlling parameters involved. Means for evaluating methods of controlling the transients are provided. The paper reports on a study using computer simulation of short circuits on: a) two "ideal" 1000 A distributions, and b) a large telephone office distribution. It considers: a) short circuits on both the primary and secondary distribution circuits, b) removal of the short with and without a fuse rupture, and c) control of transient voltage by means of capacitance.