design , installation , testing and commissioning of numerical line protection relay at switchyard at indira sagar power station , narmada nagar , distt . khandwa ( m . p . ) . isps/p/mw/2020-21/020 , supply of distance protection relay and retrofitting material as per technical spcification mentioned in scope of work annexure-a , of section-iv . , installation , testing and commissioing of supplied numerical protection relays as per scope of work annexure-c , of section-iv . , supply of of spares for distance protection relay as per technical spcification mentioned in scope of work annexure-b , of section-iv . , less buy back of rel 521 .