I am considering home plug but can not find the answer to some questions that I have. 1) The base os my house is two very small stone built (1800) cottages with 45cm thick walls. When it was converted two ring mains were installed both from the same distribution board. Will the signal be transferred from one ring main to the other? 2) What is the power consumption of each unit? 3) Can you switch them off without losing contact? Any information you can give would be appreciated.