On 20 Nov 2006 09:15:50 -0800, "
wrote:

When wiring up normal 3-prong outlets, does it matter if I switch the
black and white wires on a single outlet in the run?

I've heard the polarity doesn't matter...but want to make sure I'm not
going to short it out or something else horrible.

Also, when wiring up lights, does it matter which color wire I run to
the switch? Most of the how-to articles show cutting the white
wire...does it make any difference?

Yes, it does make a difference.

As another poster mentioned, switch on the wrong wire allows switched
devices, such as lamp sockets, to be hot - you get shocked if you touch
such items and ground.

As for outlets - those have designated hot and neutral terminals that
should not be reversed. Many appliances have polarized plugs. If a lamp
has hot and neutral reversed, then the exposed part of the base of a
partially screwed-in lightbulb will be hot - even if the lamp's switch is
off!

Also keep in mind that in some fluorescent lamps, reversing hot and
neutral can adversely affect the electric field distribution within a bulb
that is trying to start, and that may impair starting.

- Don Klipstein )