On Sat, 7 Jan 2017 16:21:42 +0000 (UTC), John McCoy
wrote:

Leon lcb11211@swbelldotnet wrote in news:Q9idnQchSrQoje3FnZ2dnUU7-
:

On 1/6/2017 3:40 PM, John McCoy wrote:

It's a variety of historical reasons. 110V is what Edison
originally used for his first DC systems (for reasons no
longer understood, that was considered "safe").

Probably considered safe because DC lost voltage quickly the farther
from the generator the lines went. IIRC there had to be a generator
within a few miles of the consumer. AC on the other hand still had
quite a bight many miles away.

AC doesn't have the same losses as DC because it can be
transferred at a higher voltage. If you sent AC from the
generating station to your house at 120V you'd have the
same losses as with DC. The wires on the utility pole
outside your house are 4600V (or something in that range,
different utilities use various distribution voltages).

Today "safe" is considered to be around 12V. I can't think
of any situation where you'd consider 110V to be "safe",
unless you're comparing it to something like 1200V.

"Safe" is considered to be anything less than 52V. There was once
talk about the automotive industry moving to a 48V battery. The
reason for 48V was that it was just below the "safe" limit. Of course
it never happened because it would have caused more problems than it
solved.