Protection Engineering Basics and Schemes Protection Engineering | Page 144

1.60 = 80TMS 3.369 2 − 1

TMS = 0. 207sec

So our setting will be, TCC = EI t = 1. 60sec PSM = 3. 369 TMS = 0. 2sec

5.4 Testing of Protection Relays:

� Pick up Test � Drop off Test � Pick up / Drop off Test � Timing Test

5.4.1 Pickup Test:

Purpose: To check the healthiness and current setting( Pick up setting / Plug setting multipliers) of Relays.

PSM =

Actual Primary Current > 1

CT Ratio pg. 144