Thanks for the fill. I had not known that some appliances were being made to ensure safety, although it sounds like there are still appliances where reverse polarity could still be a problem. (Perhaps there is a US/EU discrepancy in standards?)
ELCBs certainly sound like they are a coming thing, much like GFIs have crept into everyday life on shore and on boats, to the safety benefit of all. My research a few years ago indicated that ELCBs were experienced as problematic by skippers who wandered widely: there were lots of false tripping among those cruisers who wandered in the more marginal areas where more modern electrical installations with clean power are harder to come by. What has your experience been?
There is no question in my mind that well-built marine grade isolation transformers are the gold standard of a vessel’s shore power system. I think they are less common than might be wise because: 1. They are quite heavy awkward items that demand a not small amount of real estate, hard to come by on smaller boats, 2. They are fairly expensive, especially as there is little regularly perceived problem they solve nor new benefit readily apparent, and 3. They are probably a bit intimidating for many skippers to self-install and a marine electrician just adds to the cost.
ELCBs and isolation transformers are the kinds of safety kit that, I suspect, will not be common on boats till some regulatory agency demands them or, better still, the marine buying public educates itself on what is important and demands them.
In the meantime, I am not holding my breath and we must rely on letters like yours to get the message out.
My best, Dick Stevenson, s/v Alchemy