I think you are going to need to explain your motivation so we can better advise you. Why do you need (remote?) monitoring of the earthing? How much power do you need? What is being activated? All your goesintas and goesoutas?
I am trying to trace for an imperfect (intermittent) ground in a system that contains some PVC piping, and therefore is using a ground wire. However, there must be a corroded or loose connection somewhere. Carrying a wireless indicator while I jiggle each junction box seemed the easiest way to locate the problem.