As another poster wrote "touche"................ I've worked with electronics all my life, and am well aware of how networks of resistors work.
But not apparently how GFCI breakers or grounding systems do.
The reality in this case is that the path to ground has virtually no resistance, where your body has very high resistance.
The reality is that the impedance of the path from my kitchen floor to system ground is about 4.7 MΩ dry and about 2.9 MΩ wet. The path from my basement floor (slab) to system ground is about 2.4 MΩ dry and 1 KΩ wet.
I just now moistened my finger tips and measured my internal resistance at 229K ohms. That's wet finger tip to wet finger tip.............. do the math.
The reality is that the impedance between my left wet hand and my wet feet is 5 KΩ.
how much current is going to flow through your body??? Essentially none.
120/(1000 + 5000) = 20mA.
This assuming you have some sort of good ground. So you have your hand on the brewstand, and suddenly the element shorts out.......... Where is the path to ground?
There isn't any and of course this is not what the GFCI portion of a GFCI breaker is intended to protect against. There are magnetic and thermal trips in there too and this sort of fault is what they are for.
What the GFCI portion is there for is to protect against you touching a hot wire or terminal or touching the kettle or brewstand when there is phase to kettle leakage which is not adequately grounded by the grounding conductor because of a loose terminal screw, corrosion, a broken wire or improper grounding system installation.
You not only have a very high internal resistance, but you likely are not connected to any ground except the brew stand itself, but even if you are barefoot standing in a puddle of wort over a clogged floor drain made of iron, your relative resistance is so high compared to the grounded brew stand that there will be essentially no current flow through you...... You won't feel a thing.
You (and I coincidentally) have high body impedance (in my case doubtless because TOE has induced upon me a pretty thick skin). As noted above the resistance from my wet hand to my wet bare feet is 5K. IEC's median hand to hand, intact, dry skin impedance at 100V and 50 Hz is 1850 Ω. Even with my high Z I do feel the leakage when the impedance from the bottoms of my feet to system ground is low (basement wet, not basement dry or kitchen, wet or dry)
Again I give the analogy of the grounded pliers pulling off sparkplug wires with 40,000 volts running through them. I've done this literally hundreds of times. You can watch the spark jump to the pliers, but you don't even feel a tickle even though you are bare handed.
Again this probably reflects your incomplete understanding of grounding which probably stems from not being clear on what a 'voltage' is. It is a potential measured between two points. You cannot speak of voltage meaningfully unless you specify the two points between which is specified any more than you can specify alkalinity with out specifying the two defining pH's. In the case of a house the reference point is system ground (the point in the panel where the earth and neutral or bonded). In the automobile the reference is the car's frame. The fact that the coil voltage is 40 KV in the car's frame is immaterial. What counts here is the voltage measured between one end of you and the other. The car sits on rubber tires and that sits on the bitumen or cement or whatever. Let's say it is parked on a metal plate for simplicity. Thus the circuit is from coil (40 KV re frame) through the plasma to the terminal being pulled off, through the insulation on the wire, through the uninsulated (I assume) pliers, through you, through your shoes, through the metal plate, through the tires and back to the bottom of the coil tied to the frame. Your body's impedance is going to be pretty low compared to the series resistance of the tires, the insulation and your shoes and so only a tiny fraction of the voltage is going to present itself between the hand holding the pliers and the bottoms of your feet. Don't try this demo whilst leaning with the other hand on a metal part of the car. Source impedance of the coil will probably protect you from death but then again perhaps it won't.
This, of course, has nothing to do with a GFCI's intended function. Were there GFCI protection in the ignition circuit it would not protect you against pulling a sparkplug wire while standing on the same metal plate as the car is parked on as long as your other hand is in your back pocket. I would protect against the case where you touch hi voltage whilst the other hand is in contact with the frame.
How many of your large appliances are on GFCI?
Except for the stuff in the brewery, none.
I've NEVER seen a large appliance connected to GFCI, yet you don't cringe every time you touch your kitchen range, drier, water heater, etc.
That's because faults that a GFCI is intended to protect against aren't very likely to occur (assuming proper installation) relative to the liklihood of occurance with appliances that plug into outlets. Note that the code requires GFCI on outlets near water, damp floors etc. It does not demand them for an appliance installed in a garage because you don't as a matter of course, touch the metal on your air handler.
Even your refrigerator is usually not on GFCI, though 120 can kill you just as dead as 240.
Now my refrigerator has a stainless door and where it sits (floor impedance of 2.9M wet) one would be of little use. Now were I to move that fridge (for its retirement) to the basement where floor impedance is 1K to earth if the sump pump fails I would install a GFCI for the outlet into which it would plug as, in fact the 2017 code would require me to. Also with respect to 120/240 - there is no potential in a normal home in the US which is greater than 120Vrms with respect to reference.
I'm not against GFCI except in so far as it leads to the mindset that whatever I do GFCI will protect me. A person should always design something like a brew stand as if
GFCI didn't exist.
Yes he should! And the code requires it. It does not offer the the option of installing a proper grounding system or installing GFCI breakers. It requires both (for certain locations). GFCI has an important potentially life/injury protection function. You need to understand what this is (and isn't) and how building grounding systems work. Clearly you have some distance to go here but, if it is any comfort, not many people, including professionals, really understand grounding.