On Nov 16, 12:59*pm, David Nebenzahl wrote:
On 11/16/2010 9:40 AM LSMFT spake thus:

wrote:

I have some power equipment that needs a new cord.
The current cord has only 2 prongs.
Can I buy a 3 prong power cord and just attach the ground to the case
of the power tool? *Is this what the 3rd prong does?
Would this make is safer?

Does a GFCI also work on a power tool with just 2 prongs?

Two prong plugs are polarized and are grounded to the neutral line.


Two prong plugs on modern tools are double insulated, don't have metal
housings and are not grounded to the neutral, which is a current
carrying conductor.

The answer to the original question is it depends. If it's an old
tool that is not double insulated and UL listed with a 2 prong plug,
then installing a new 3 prong plug and connecting the ground wire to
the metal housing might make it safer. But even that depends, because
we don't know how the tool is put together. For example, if there
were two seperate metal parts of the tool that are not connected
together, then you could be only grounding part of the tool.

In any case, a GFCI will work with it in any case and provide a safe
solution.







No, not necessarily. My Craftsman circular saw, f'rinstance, has a
non-polarized 2-prong plug, 'cause it's double insulated. No need for
polarization.

--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)