You will not find a single North American-market tool where this (55V to ground) will make a difference.
Historical curiosity:
I have an old book (House Wiring, by Thomas W. Poppe, 1930), which describes two ways of grounding a 120V appliance through the cord. The first way is pretty similar to the way we do it now. The second is by bonding the cord neutral to the appliance frame. A special polarized plug needed to be used, which was incompatible with the standard USA parallel-blade plug (now known as NEMA 1-15). This would have been a field modification and could not possibly have been very common. You wouldn't see it at all nowadays, since anyone ignorant and crazy enough to do this is also ignorant and crazy enough to omit grounds altogether.
Our equipment grounding (protective earthing) is exactly the same inside the appliance as yours is.
In fact, we have the same 60/120V center ground transformers here. They are a recent development, permitted by Article 647 for sensitive electronic equipment. This article originated in the 2002 NEC.
