On Jun 29, 12:34 pm, wrote:

Seems the US developed a long lasting wiring system long before we
did. It wasnt until ashathene and pvc cables in the 60s that we
finally got cables of types that would truly last long term. So old
wiring here is almost invariably highly risky, in a very bad way and
only very occasionally encountered at all.

The main old types here are
- cotton/rubber, and its normal for the insulation to have perished
and fallen off in places, and not just at the ends.
- lead sheathed rubber insulated from 1930s, the ends of which get
into a state.

That is just the half-of-it. We have had NEMA (National Electrical
Manufacturers Association) standards for pretty much all of present
living memory such that appliances (AC & AC/DC) manufactured in the
20s are compatible with receptacles and ratings today. For instance,
1920s-installed duplex receptacles will accept fat-blade neutral
(polarized) plugs that are today's standard. One can 'call out' by
NEMA number a receptacle and plug that are specific to, and compatible
with both the load and application, from isolated-ground hospital-
applications to heavy-load vibration-proof applications, one, two
(yes, there is still 4-wire/2-phase power applications in the US) and
three-phase. And, be assured that that unit and/or combination will
fit and be acceptable anywhere in the US. One example I claim is a
1928-model Sky Rover radio with a tri-voltage switchable power-supply
(105/110/120V) and a standard NEMA-labeled plug. About a year-and-some
after NEMA's inception.

http://www.nema.org/about/history/

On a related note, IMAGINE purchasing an appliance with no plug on
it... on the premise that what is in your house is not the same as
next door, or next door to that. AND THEN... the home-owner is
expected to purchase said plug compatible with their specific system,
THEN to install it correctly. This was the common state of affairs in
parts of Europe until not so long ago.

Fascinating also that every country in Europe seems to have a
different standard for receptacles, wiring, fusing and so forth. Y'all
do need standards if only to allow cross-border commerce much less
reduce costs and enhance safety.

Peter Wieck
Wyncote, PA