Distance Protection - Quad or Mho and Why?

[DTR2011]

Let's assume we are talking about modern digital relays here. It seems in North America the Mho is preferred and in other countries the Quad is. My guesses would be historical preference or comfort.

I am aware that the Quad offers better resistive coverage.

My experience is that the Mho is far easier to set and test.

 

[vandal06]

That's my understanding as well. I've set a Quad on a couple of occasions to match existing philosophy and for most applications I find the extended resistive coverage is just not worth the headache of developing settings, especially when phase/ground mho with a backup 67N is so effective.