They seem to have a policy that 25s are for one house, 37.5 for 2 houses and 50s serve 3 houses, just based on driving around my neighborhood and looking. These are "all electric" homes tho with no other energy utilities available. I still find looking at transformers can tell you a lot of what to expect when you get your meter out. I figured that out after that "Delta Vee" fiasco 30 years ago when we were blowing power supplies left and right at one company. I learned to spot this configuration right away

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Greg Fretwell