Stray Currents from dc Railways

Stray Currents from dc Railways 15.2.1 Regulations for dc Railways... 

Before preparing a CP design, it must be known whether or not stray currents are present. Currents which will most severely affect the structure to be protected are apt to be those of substantial magnitude that continually vary in quantity. These include stray currents from DC railway systems, mining operations using EXT power, DC welding operations, and similar sources. 

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