140428-1000 EDT
In our area there are high leg deltas all over the commercial areas. Easily spotted by two transformers, one large for the single phase lighting loads, and one small to supply the air conditioners, or in our case CNC machines. When three transformers are present it takes a closer look to see that it is a high leg delta.
In my residential neighborhood, one block radius, there are at least two high leg deltas. In one of these homes there is a three phase panel and a separate single phase panel.
In the shop we use two pole, or single pole breakers for single phase. Some of the three phase panels have single phase loads with blank spaces.
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