In an inverse definite minimum time, electromagnetic type over-current relay, the minimum time feature is achieved because of

The plug setting of a negative sequence relay is $$0.2$$ $$A.$$ The current transformer ratio is $$5:1$$. The minimum value of line to line fault current for the operation of the relay is

In a thermal power plant, the feed water coming to the economiser is heated using

Out of the considerations (i) to (iv) listed below,
(i) No distance limitation related to steady state stability
(ii) No reactive power requirement from the system at the two terminals
(iii) No substantial effect on fault level of the two systems at the terminals inspite of the inter connection
(iv) no corona problems
The considerations which constitute advantages of HVDC transmission are