Reverse Power Relay Problem.

WE have Installed New 750KVA T/C and IT's HT ,LT panel and Overhead Line (4KM) for our Construction Load of Township.

In LT Panel there is a ACB (L&T U Power 2000Amp) and 6 Distributed Feeder ( Min 250 Amp and Max 600 Amp).

We are Facing Following from In LT panel.

=When we charged T/C and HT and LT panel at first time We got announication of RPR Relay (c&S, Bp1-R ,5Amp). After reseting The Relay We charged Distribution Line.

= Right Now in Distribution Line Load is very Low Total Load on LT Panel is 100Amp and LT panel works well.

=But After Thee Day We are facing a problem when Power supply from Uper stream (From Power Supply Company) goes out at that Breaker goes OFF . When Supply goes ON from Uper stream We get Announciation of RPR .

= At that time We have to reset the RPR Relay and ON the ACB and Power remains Stable. We have observed that Only When Supply of Uper Stream goes OFF we get Announciation of RPR otherwise nothing goes wrong from RPR Relay.

=We belive that due to heavy inrush current RPR may operate but When supply goes of ACB goes OFF and when We get supply from uper stream at that Time Distribution Load is not in Picture (ACB OFF at that time) eventhough RPR goes ON ???

=We have also incrase setting of PR> from 5% to 20% (Max 30% in dial) and Time Delay from 5 Sec to 20 Sec but Still problems is continious.

What should we do?