"Let me elaborate on my first
"Let me elaborate on my first point on safety:
In a typical wiring scenario (including all US homes, industry, and boats without an isolation transformer), if you grab the stripped back black wire conductor and stand in a pool of salt water, you may likely die. There are a couple of popular mitigations for this, one being active and that's called a GFCI; a ground fault circuit interrupter. Here you will will get a short duration shock, up until the internal relay opens. An even better way around the hazard is to use an isolation transformer, and leave the secondary floating (ungrounded). Now, you can grab the hot conductor, stand in salt water, and not be affected by a shock. This is because the transfomer removes the ground reference from the circuit, voila, there can be no ground current. You still have 120VAC across BOTH output terminals, but no current can flow from either terminal to ground. Isolation transformers are $$, and that's why homes do not use them. The Navy does, and this technique also allows a somewhat fault tolerant operation. If a single phase conductor should touch steel, no circuit overload will occur, and the loads continue to operate. In a battle damaged wireway supplying bilge power, that could be important. Also, wires running in a classed environment, such as a magazine can sustain a single short to ground without sparking. To make this long story longer, there is a detection setup installed at the power panel, which had consisted of a light bulb per phase, that indicated normal, ungrounded conductor status. When the tech sees the unbalance, they send a crew to find the fault. Meanwhile, the system continues to supply power, the electrical loads non the wiser!"
