On Wed, 07 Sep 2016 13:58:15 -0400, wrote:

On Tue, 06 Sep 2016 23:24:25 -0400, wrote:

On Tue, 06 Sep 2016 23:00:41 -0400, wrote:

On Tue, 06 Sep 2016 20:45:48 -0400, wrote:


Uh huh.
You understand the listing standard allows up to a second before the
circuit is open and during that time, you are getting full circuit
current, whatever skin contact will pass.
The UL class "A" spec is no trip at 4ma, must trip at 6ma, with or
without load connected, and it must trip with a 2 ohm grouinded
neutral and within 25ms on a 500 ohm fault. (240ma).

The spec may ALLOW up to a second, but I have never found that spec
(inless you are talking the old IEC 20ma trip device. (which does NOT
protect against shock)

I've had GFCI outlets trip without even feeling the shock - might be
a case of "no sense no feeling" as 1 ma is supposedly the threshold
for feeling a shock

4ma is not supposed to trip it at all but it might cook off
eventually.

This is in U/L standard UL943
(CSA C22.2 No. 144.1 and NMX-J-520-ANCE-2006)

The spec is T=(20/I)
T equals time in seconds
I equals current in milliamps.

Right at the threshold it might take 3 or 4 seconds.
At 100ma it will trip in 200ms.
That is plenty of time to get quite a jolt.
You are still dealing with a fairly complex mechanical linkage,
particularly in the breaker model and that takes time, even if the
fault is detected immediately.
I have worked with lots of high speed relays (1-10 ms) but this ain't
one of them
A QO GFCI
That is a big, slow solenoid and you are moving lots of metal.
http://gfretwell.com/electrical/gfci.jpg
I doubt it would actually open in less than 20 ms with a half an amp
and it is hard to get that much current through your body if you not
standing in the rain barefooted.
In other words the damned things are next to useless as a "safety
device" The ones I have had trip were not the breakers, but the
Leviton? outlets - and an inline 2 wire polarized plug type unit (I
think it was the same as one I have here that is made in Korea -
Wellong P8S E130151 molded into the plug.

They will shut down the circuit before you are seriously hurt but you
will still get a wake up call. Bear in mind the higher the current the
faster they trip, down to the time it takes to physically trip the
device.