Question about GFI in a specific situation...

[EasyGoing1]

I have a friend who was being stupid ... something about using a microwave oven transformer to carve images into wood ... I don't really know the details, but as she was preparing things based on something she saw online, she had either one or two hands on the transformer leads (I don't know if it was one or two hands, and she currently has no memory of the incident) when someone else plugged the microwave into the wall outlet, electrocuting her.

She had to be resuscitated three different times, spent a couple of days in ICU, and is at home now recovering from the incident.

My question is, would she have gotten zapped as badly had the socket that the moron plugged the microwave into been a GFI outlet?

[stj]

Re: Question about GFI in a specific situation...

the transformer balances the load, a device like that wouldnt have tripped.
she was using high voltage arc's to cut tracks in the wood - you arent supposed to even be near it when you power it up!!

[kaboom]

Re: Question about GFI in a specific situation...

GFCIs will not prevent shocks from the secondary of a transformer.
Nor will they protect against hand-to-hand shocks (w/o ground faults) on the 120 side..

[redwire]

Re: Question about GFI in a specific situation...

What a tragic accident.
GFIC works by summing the current flowing out through Hot, and flowing back in from the load on Neutral. The sum should always be zero.
I out (hot) = I return (neutral). So actual ground current is not measured, it's inferred through math.
With a ground fault, the current passing through (a person) to ground leaves a net imbalance of several mA and the GFIC trips.

MOT normally has one leg of the secondary riveted to the core, which should be chassis ground, at least it is in a microwave oven. This secondary ground might be lifted and floating, to do the woodburning. Instead of one wire that is hazardous live, there would be two wires. Or one is a ground. Is it even a three-conductor mains cord. Have to see details of the setup.

I think a GFIC would false-trip due to the arcing on the wood. They are designed to monitor 50/60Hz currents and an arc has high frequency components so the current sense would be noisy and not accurate.

There's really no safe way to mess around with high voltage and high current unless you have the linesman gear PPE - gloves, boots, cattle prod etc.

[Per Hansson]

Re: Question about GFI in a specific situation...

My question is, would she have gotten zapped as badly had the socket that the moron plugged the microwave into been a GFI outlet?

As others noted "it depends"
But to add another point: a GFCI outlet trips at around 20mA here in Europe.
I know in the US you have lower rated ones.
But since we are dealing with a high voltage transformer you have to take that into account.
So with 19mA flowing through the primary to ground (or any other way than back via Neutral) nothing will trip.
This is still waaay more than enough current on the secondary (high voltage side) of a microwave oven transformer to kill you.
There is a reason they have all of those safety nets when installed in a microwave oven.
And at least all serious videos on Youtube that discuss this topic begin with a lengthy discussion about how dangerous they are!

As stj said: if you use such a device you are not in any way near it when it is powered up: it is just too dangerous!

[EasyGoing1]

Re: Question about GFI in a specific situation...

the transformer balances the load, a device like that wouldnt have tripped.
she was using high voltage arc's to cut tracks in the wood - you arent supposed to even be near it when you power it up!!

Well, I'm assuming she was trying to get things ready when it was plugged in ... the person who plugged it in is a total moron ... I've had her blocked on my Facebook for a few years now, though I can't remember why ... I just know she's a total moron - and this incident only offers more evidence to that fact.

[EasyGoing1]

Re: Question about GFI in a specific situation...

It's also strange that she has not recovered any memory of the incident at all. I wonder if the electrocution affected her conscious brain at the time it happened and scrambled those neuron transmissions so that she will never have a memory of it ... I've never heard of that happening with electrocutions before.

It's been about a month now since it happened.

[stj]

Re: Question about GFI in a specific situation...

we are electrical,
just ask the cia - they spent enough time fucking peoples heads up this way!!!

[EasyGoing1]

Re: Question about GFI in a specific situation...

we are electrical,
just ask the cia - they spent enough time fucking peoples heads up this way!!!

Yeah ... with electricity ... and LSD and god knows what else they experimented with.

[sam_sam_sam]

Re: Question about GFI in a specific situation...

First of all you need to understand what you are doing and how dangerous things can get if you are sloppy with what you are doing with this being said

It could be done safely if you were to follow some common sense safety precautions
Like wearing electrical safety gloves
Like wearing safety green glasses
Not working in a wet environment
Working on a plastic work table
And the most important thing is that you know what you are doing and the safe way to do it
If you design this device your self and you do not have safety switch that requires you to activate the device your self not just plug it in to the wall to turn it on and that it requires you to activate the circuit with two switches on the insulated probes to keep accidentally turning on the device to keep accidents down to a minimum until you are ready to work with the tool

This is a problem with information that is provided by YouTubers that provider of information on how to do things

I have seen some real questionable things on YouTube before but I guess because I have worked in a industrial plant setting before and have had a lot of safety training before I can spot what is safe to do and what is not safe to do

I have personally seen what high voltage can do to a living tree and it was not pretty what happened to it before the power line jack fuse blew and stopped the power supply to the tree

[stj]

Re: Question about GFI in a specific situation...

it would be best to show the woman some electroboom video's.
specially the one where a jacobs ladder falls on him while it's running.

then she wont fuck with high voltage again.