Typically, 5A secondary although 1A secondary is available. Can be single or multi ratio (MR). Rule of thumb, select a ratio slightly larger than the rating of the circuit to be protected. Numerical relays have more forgiveness than induction disk. Graduated with a Master of Science in Electrical Engineering from The University of Texas at Dallas in 2018 and with a Bachelor of Technology in Electrical and Electronics Engineering from VIT University, Vellore, TN, India in 2016. The objective of this presentation is to convey a basic. presentation of protection and control relaying. For example, unselective protection operation during a medium voltage network fault will cause an outage for an unnecessarily large number of consumers.
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