On 12/14/2012 3:09 AM, Tim Watts wrote:
Doug wrote:

I believe most of my outlets are wired in one series to a GFI outlet
in my garage but I'm not sure of the outlet beside my garage door
opener. Is there a way to tell if this outlet is also protected?

Also, is there a difference between a GFI outlet and surge protected
outlet ? Keep in mind, I'm far from a electrical guru so easy words
pleasegrin.


NOT A SERIOUS SUGGESTION
========================

If you are brave:

Wire a resistor with a value about 3000 ohms between line/live and
ground/earth and plug it in.

Assuming this is a 110-120V outlet and the GFCI is set at 30mA this should
cause the GFCI to trip out (it would cause a current imbalance of about 35mA
RMS which is a little more than a 30mA GFCI would be looking for. Adjust
resistor if your GFCI is differently rated.

If there's no GFCI and the resistor has a power rating less than about 3-4W
it's likely to act like a fuse and explode.

This is NOT an entirely serious proposition unless you are careful but it
would make a fairly valid test and show that the GFCI was tripping at the
right amount of current imbalance.

I would not be surprised if there was a ready made plug version (safely
designed) that you could buy.

In fact:

http://www.ebay.co.uk/itm/Sperry-GFI6302-GFCI-Outlet-
Tester-/290770585838#vi-content

Looks like a variation on the classic neon based socket-wiring verifier.
Only $18. Worth having I would say - GFCIs (or RCDs as we Brits call them)
are prone to failure and sticking. At the very least, push the test button a
couple of times a year as routing maintenance.

Of course, it does not tell you that your GFCI is tripping in the required
time - for that you need a fancy tester.

GFCIs are supposed to be tested periodically. I usually test them when I
will be depending on one for protection. The built-in test is the same
as your resistor test above - a resistor is connected from the
downstream hot to the upstream neutral (or vice-versa?). The test works
even when there is no ground at the GFCI.

This side the pond GFCIs operate at 5mA (4-6).
If I remember right, there are some ground fault detectors for equipment
that operate at 30mA.

Would think you would get a nasty shock at 25mA with no RCD trip.

I certainly don't want to chase you away, but a good usenet group for
the UK (which you may have discovered)is
uk.d-i-y
It is astonishing how different the electrical is in the US and UK -
like ring circuits, and RCD mains.