Re: Question about reversed-polarity in an AC outlet

From: Sam Goldwasser (sam_at_saul.cis.upenn.edu)
Date: 02/22/05 

Date: 22 Feb 2005 08:39:49 -0500

"ChrisCoaster" <ckozicki@snet.net> writes:

> Since this is the oldest post with a reply option in Google:
>
> To Sam Goldwasser who stated:
>
> >>There is no obvious way for this to happen. Normally, modern
> equipment doesn't
> care about the polarity of the Hot and Neutral, even in terms of
> safety. (By
> regulation, it must NOT affect safety<< snip snip
>
> Modern equipment doesn't care about the polarity of Hot and Neutral,
> ehh? Then why in the instruction manual for many appliance and AV
> equipment, and sometimes on the cord itself is stated:
>
> "One blade of this power cord is larger to fit only one way into modern
> power outlets. Do not attempt to alter or disable this safety
> feature".
>
> Sam if you have not seen this warning, welcome to the 21st century - or
> at least to the 1980s!

Welcome the world of litigation. :)

>From the point of view of user safety, it shouldn't matter.

There will be some differences like whether the shell or center of a
light bulb socket is electrically live if the switch is off. So, I guess
if someone were to get electrocuted changing a light bulb with the plug
reversed, they couldn't sue. ;-)

There will be some issues with RFI if there are line filters in the
equipment. There may even be a tingle from slight leakage due to
the line filters if the plug is reversed, but it's not dangerous.

But, otherwise, it should operate normally and the user of the equipment
can't get hurt using it in a normal way.

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