The current-carrying capacity of lead-covered cables

This article gives data whereby the carrying capacity of lead-covered cables can be calculated on the basis of thermal limitations. Carrying capacity as limited by voltage drop or economical considerations is not discussed. The article shows how further data can be applied as these are determined. An appendix contains some numerical examples illustrating the use of the data. It also contains a chart by which it is possible to determine graphically, for given conditions, the carrying capacity of three-conductor paper and varnished cloth cables installed in conduits. There is also included a chart illustrating the relation between the various temperatures and temperature rises of a group of lead-covered cables.