Neutral Monitoring Relay for NGR

In one of my projects we were feeding the entire plant by means of 3MVA, 6.6kV,Dyn11 Transformer. This Transformer is Resistor Grounded ie., Neutral Grounding Resistor (NGR)for which a we have provided Netural Monitoring Relay (NMR). Inside the NMR there is a sensing Resistor which is of rating 5kV, if we change the rating of sensing resistor to 15kV is there any problem w.r.t operation of the NMR. Please guide me in this regards.
Neutral Earthing

asked 12/12/2011

2 Answers

Thank you Sir.
answered 12/16/2011 Keshavanarayana.G 3
I don’t believe there would be an issue with the voltage. The resistance needs to be the same as the NMR will be measuring the circuit through the sensing resistor and NGR. Given the voltage level, I would also confirm this with the NMR manufacturer just to be on the safe side.
answered 12/15/2011 Steven McFadyen 246
Steven McFadyen

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