I have not found a straightforward explanation on how to perform voltage drop calculations for cables used for instrumentations purposes. Suppose you have Current Transformer (CT) and Potential Transformer (PT) connections coming into a relay (IE SEL421). If we have a cable that runs from the yard equipment to the panels, let's say 300 Feet, using a #9 cable rated at 0.000729 ohms/ft, and we want the CT current to be 5A and the Potential coming into the relay to be at 67V, how do we determine this?(adsbygoogle = window.adsbygoogle || []).push({});

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# Voltage drop calculations for CCVT's and Current TF's?

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