GFCI breaker in panel vs spa panel

[Owly055]

Here's a case where GFCI saved my a$$. I had a commercial, 120V, off the shelf, UL listed hotplate that I used under my mash tun to help maintain heat. One day, after about 10 uses, it developed some internal open and placed 120V main directly on my SS mash tun. The tun was isolated from ground and had no leakage that the GFCI could immediately pick up on. I did not realize this until I made full contact on this tun and the GFCI popped as designed, only after a very brief holy s*** moment as full 120V ran from one hand, through my body, and heart, to the other hand resting on another pot that was thoroughly grounded.

I am not a commercial electrician but do have background and schooling in both AC and DC electronics and understand the concepts fairly well (in my youth I fixed common household electronics including televisions with 15kv+ 'flybacks').

Going without GFCI and any other safety technology on any such brewing equipment is simply asking for disaster only to save a few bucks. Just don't do it. 120V AC will kill you in an instant. It is irresponsible to suggest that anyone reduce the presence of safety devices to save a few bucks because some unrelated and carefully tested commercial devices may not have those same devices (and yeah, BTW, the electric water heater I just installed 3 months ago had a GFCI built in).

Brew on, safely

Your hotplate situation is far different from what we are talking about........ I'm not anti GFCI. I'm anti ignorance. GFCI is not and should not be a substitute for good electrical design. Your mash tun with a 5000 watt element running on 240 MUST BE GROUNDED and if it is grounded, there is virtually no risk. People get electrocuted when an appliance falls into the bathtub with them, but never from a shorted element in the water heater or electric stove. GFCI if it works correctly will trip on any imbalance. It's extremely unlikely that your hotplate was dead shorted to the pot, or that you were a good ground path.

Again, I'm NOT anti GFCI. I'm anti poor design and strongly oppose relying on GFCI in lieu of proper design. If you are afraid of your system without GFCI, then you should be afraid of it WITH GFCI. It's not a pancea. It's not a substitute for good design or common sense. While I don't have a single GFCI outlet or breaker, I've installed both for other people numerous times, as well as wiring up hot tubs for people as recently as a few months ago........

H.W.

 

[augiedoggy]

Electricity can be dangerous, but ignorance is ALWAYS dangerous.


H.W.

Yes and thats one of the reasons GFCI units are required for this type of application and all similiar uses that meet the same criteria of people working with electrical appliances near or with water.. Accidents and mistakes happen. Even electricians die from them. It is another measure of safety. A 240v element will continue to work if the ground connection fails.. and we all know you can try to avoid problems as much as possible but mistakes or failures can still occur a ground wire can break loose in a plug there are not of ways it could end badly.

and my hot tub has a ground... why was I required to install a gfci if its pointless? by the time the breaker popped from the ground I would already be dead. at least with a nearby gfci the chance of survival goes up.

 

[itsnotrequired]

Electricity can be dangerous, but we survived many years without GFCI, and electrocution was rare. People worked in restaurants and factories with high voltage and accidents were extremely rare.

in the 1970s, reported electrocutions associated with consumer products was on the order of 500-650 cases a year. there were very few gfci devices out there. fast forward to the 2010s and there are millions upon millions of gfci devices installed. electrocution rates are on the order of 100-200 cases per year. considering the us population has increased about 60% since the 1970s, those rates are even more impressive. gfcis have clearly resulted in increased safety.

i mean, we 'survived' without gfcis for years just like we 'survived' without seat belts and air bags...

 

[Owly055]

I'm NOT anti GFCI ................. I've repeatedly explained that it is NOT a substitute for good design. I see a mindless reliance on technology here that disturbs me.

H.W.

in the 1970s, reported electrocutions associated with consumer products was on the order of 500-650 cases a year. there were very few gfci devices out there. fast forward to the 2010s and there are millions upon millions of gfci devices installed. electrocution rates are on the order of 100-200 cases per year. considering the us population has increased about 60% since the 1970s, those rates are even more impressive. gfcis have clearly resulted in increased safety.

i mean, we 'survived' without gfcis for years just like we 'survived' without seat belts and air bags...

 

[itsnotrequired]

I'm NOT anti GFCI ................. I've repeatedly explained that it is NOT a substitute for good design. I see a mindless reliance on technology here that disturbs me.

H.W.

but even good designs and proper installations can fail. or be used improperly. that's the whole point of circuit breakers, minimum conductor sizes, etc. it isn't a 'mindless reliance on technology' and is in fact the opposite: good design. folks don't drive cars like lunatics just because their cars have airbags just like folks don't grab bare wires just because there is a gfci on the circuit.

 

[Owly055]

The first object of a ground is to provide a path to ground, not simply to trip a breaker......... It's to provide a path of least resistance for electricity so you are not that path. I recently gave an example of this with my grounded pliers for pulling spark plug wires of on a running vehicle. HEI ignition (modern electronic ignition) runs 40,000 volts.

I've said before several times that I'm not against GFCI, I'm against poor design, and I'm against relying on GFCI in lieu of good design. It's a "court of last resort", not something to rely on. Kind of like a parachute or an airbag. Seatbelts, airbags, and insurance seem to have made people drive stupidly. Every time I go to the city I see cars driving with half a car length between at 75 miles per hour.....millions of them it seems. I call that stupid. It may be stupid not to wear your seat belt, but it's far more stupid to drive like an idiot.

If you are afraid of being electrocuted by your system without GFCI, then you shouldn't be using the system at all. Design as if GFCI didn't exist

Your point about a faulty ground is an example of why good design is necessary. You are relying entirely on a power cord for ground. That's poor design. in this situation. Good design is to have the brew stand itself grounded independently. Again, if I'm afraid of it without GFCI, then I need to address safety, not just hang a GFCI on it like a bandaid.

H.W.

Yes and thats one of the reasons GFCI units are required for this type of application and all similiar uses that meet the same criteria of people working with electrical appliances near or with water.. Accidents and mistakes happen. Even electricians die from them. It is another measure of safety. A 240v element will continue to work if the ground connection fails.. and we all know you can try to avoid problems as much as possible but mistakes or failures can still occur a ground wire can break loose in a plug there are not of ways it could end badly.

and my hot tub has a ground... why was I required to install a gfci if its pointless? by the time the breaker popped from the ground I would already be dead. at least with a nearby gfci the chance of survival goes up.

 

[augiedoggy]

You keep saying your not anti gfci but your earlier comments kind of imply they are foolish and unnecessary and only used as a band-aid instead of proper design when in fact they are a requirement of "proper" design.. Just because they are implemented doesn't say anything against the intergity of the design they are part of where as the opposite case where they are not utilized are more often an indication of the type of shortcuts and improper design that might accompany a dangerous situation.

I can recall having this discussion a few years ago with another fellow who kept saying they were unecessary.. only his control panel was comprised of an SSR , PID and wires nailed directly to one of the wooden rafters directly above his boil kettle were the steam collected.. he though enclosures were unecessary too.. the reality is most of the people who don't use them skip them because they are too lazy or cheap to do so.. others just think they know better and such things don't apply to them and sometimes arrogance can be just as dangerous I think too. Your statements can easily be taken to heart by a reader here who is looking for guidance here and doesn't end up so lucky. This isn't an electricians forum it's a homebrewing forum. Most of the folks here may be consuming alcohol while using this equipment to make more.. it's better to make the thing as accident and foolproof as possible.

 

[John Eberly]

QuoteThe problem here is ignorance of electricity, which breeds fear of electricity. Electricity can be dangerous, but we survived many years without GFCI, and electrocution was rare. People worked in restaurants and factories with high voltage and accidents were extremely rare.Quote

Not so. If this were true there would have been no reason to invent and deploy ground fault circuit protection. Electrical improvements in equipment and requirements of codes have always been driven by accidents, fires, and the case studies that came out of these events.

You may feel that your approach is justified because of your not-very-applicable experience, and maybe that will keep you from doing something stupid. I'm not convinced, but then I admit I don't really know you.

I do think that you should avoid advocating for your oh-so-contrary opinions when others might make the mistake of taking you seriously. Many of the readers on this forum have, let's say, less understanding than you do of electricity. Save your devil-may-care attitude for yourself and don't encourage others to take risks that they don't understand.

 

[ajdelange]

Looks as if it is time, yet again, to explain what a GFCI does. It's sole function is to ensure that all current that issues from it returns to the source through it (and its wiring) and not through some other path. If current returns through a path other than the wires connected to the breaker that is potentially not good as the other path could be (but is not necessarily) you. The abbreviation in the US stands for Ground Fault Circuit Interrupter. The POMs call it an Earth Leakage Circuit Breaker. This makes it clear what sort of fault (a path from your equipment through you to ground) it is intended to protect against.

 

[passedpawn]

I'm completely rational, have been working with high voltage electricity for over 50 years including working in the field with centerpivot irrigation systems that run on 480 3 phase which have no such protection. I'm very well aware of the risks of electricity and water. As the previous poster said, you are NOT submerged in wort. I submit that it is you, not I who fail to understand electricity. People do not get electrocuted dealing with properly grounded electrical devices. There is one simple rule with electricity.... It takes THE PATH OF LEAST RESISTANCE to ground. If an element shorts out for example inside a boil vessel and the system is properly grounded you can handle the vessel and never even get a tingle. Heating elements are in metal tubes, and even if one did short out somehow, the path of least resistance is through the metal not you.

Let me give you a real world example of extremely high voltage and grounding. Nearly everybody has pulled a spark plug wire off and gotten nailed with very high voltage.. I made a pair of grounded pliers years ago and still use them. Put the ground clamp on the engine or body of the vehicle, and you can grab plug wires with the pliers bare handed all day long and never get even a tickle. You can watch the spark jump to the pliers you are holding, and never feel anything.

Please explain to me where these huge risks are?? I personally would never even consider GFCI for a boil kettle...... I'm not bathing in it. I would however have a good ground and verify that my ground worked, a simple matter of touching your VOM to each hot lead and to the kettle. Each should read 120 volts. If your kettle is grounded, you could plunge the bare ends of a live 240 volt cord into it, while having your tongue on the side of the kettle and standing in a pool of wort barefoot that was draining down your floor drain and never get a shock.

The problem here is ignorance of electricity, which breeds fear of electricity. Electricity can be dangerous, but we survived many years without GFCI, and electrocution was rare. People worked in restaurants and factories with high voltage and accidents were extremely rare.

Electricity can be dangerous, but ignorance is ALWAYS dangerous.

Your assumptions and conclusions are beyond insulting......... I work with electricity and water all the time, and know how to protect myself......... You obviously have little or no real world experience or knowledge. Spreading fear and ignorance serves nobody.

H.W.

Without going into my qualifications, I do understand electricity well. I do work with it every day. I've been working with 600VAC in the last month. It's my job Owly. In fact, it's pretty much all I do.

 

[ajdelange]

I'm completely rational... There is one simple rule with electricity.... It takes THE PATH OF LEAST RESISTANCE to ground.

If you believe the last sentence that proves the first to be untrue. Given a set of paths p1, p2, p3... and an impressed voltage of E across each of them the current that flows through each is I1 = E/R1; I2 = E/R2; I3 = E/R2... where R1, R2 and R3 ... are the resistance of the paths. The current does not select the path of least resistance. It divides itself among the paths according to their resistances. In the current example we might have a heater in a circuit with resistance such that 50 amps flows through it with, in this example, the resistance being 240/50 = 4.8 Ω. This is clearly less than the resistance of a path consisting of someone with dry unbroken, skin to ground which is perhaps a couple K Ω. At 120V (we've got a bi-phase system here) that means a current of only 60 mA. Thus not all the current takes the path of least resistance. 60 mA, a very small fraction of the current, takes the much higher resistance path through the person contacting the hot wire. Though it is not a large amount of current it is, nevertheless, enough to do you a mischief.

The function of the GFCI is, of course, to detect that the high resistance path is there and remove power from the circuit thereby relieving the insurance company of the burden of having to pay out a benefit. The code requires GFCIs in certain locations for a good reason. It is written by the insurance companies.

 

[doug293cz]

If you believe the last sentence that proves the first to be untrue. Given a set of paths p1, p2, p3... and an impressed voltage of E across each of them the current that flows through each is I1 = E/R1; I2 = E/R2; I3 = E/R2... where R1, R2 and R3 ... are the resistance of the paths. The current does not select the path of least resistance. It divides itself among the paths according to their resistances. In the current example we might have a heater in a circuit with resistance such that 50 amps flows through it with, in this example, the resistance being 240/50 = 4.8 Ω. This is clearly less than the resistance of a path consisting of someone with dry unbroken, skin to ground which is perhaps a couple K Ω. At 120V (we've got a bi-phase system here) that means a current of only 60 mA. Thus not all the current takes the path of least resistance. 60 mA, a very small fraction of the current, takes the much higher resistance path through the person contacting the hot wire. Though it is not a large amount of current it is, nevertheless, enough to do you a mischief.

The function of the GFCI is, of course, to detect that the high resistance path is there and remove power from the circuit thereby relieving the insurance company of burden of having to pay out a benefit. The code requires GFCIs in certain locations for a good reason. It is written by the insurance companies.

Touche!

Brew on

 

[itsnotrequired]

in fairness to owly, code doesn't explicitly call for gfci protection for electric brewing systems. code calls out specific requirements for gfci protection and it is limited to 125 volts, 15 and 20 amp receptacles in specific locations. so if you are running a 240v system, code does not require gfci protection. applications that would require gfci protection by code would include 120v systems that are plugged into receptacles which require gfci protection (e.g. kitchen countertop, outdoors, garage, etc.) it doesn't matter if you are plugging in a brewing controller, appliance, power tool, whatever. the receptacle itself requires gfci protection so your brew controller will have the protection.

all this being said, code describes minimum requirements only. absolutely nothing wrong with adding gfci protection where it is not required. it is of course not a substitute for proper wire sizes, proper installation techniques, good electrical practices, etc. but man, it sure is some cheap insurance.

 

[Owly055]

As another poster wrote "touche"................ I've worked with electronics all my life, and am well aware of how networks of resistors work. Most folks here are pretty ignorant about electricity, hence the oversimplification......The reality in this case is that the path to ground has virtually no resistance, where your body has very high resistance. 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. One resistor at essentially zero ohms, another at 229K ohms.......... 50 amps flowing to ground, how much current is going to flow through your body??? Essentially none. 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? 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.
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.
How many of your large appliances are on GFCI? 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. Even your refrigerator is usually not on GFCI, though 120 can kill you just as dead as 240.

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.

H.W.

If you believe the last sentence that proves the first to be untrue. Given a set of paths p1, p2, p3... and an impressed voltage of E across each of them the current that flows through each is I1 = E/R1; I2 = E/R2; I3 = E/R2... where R1, R2 and R3 ... are the resistance of the paths. The current does not select the path of least resistance. It divides itself among the paths according to their resistances. In the current example we might have a heater in a circuit with resistance such that 50 amps flows through it with, in this example, the resistance being 240/50 = 4.8 Ω. This is clearly less than the resistance of a path consisting of someone with dry unbroken, skin to ground which is perhaps a couple K Ω. At 120V (we've got a bi-phase system here) that means a current of only 60 mA. Thus not all the current takes the path of least resistance. 60 mA, a very small fraction of the current, takes the much higher resistance path through the person contacting the hot wire. Though it is not a large amount of current it is, nevertheless, enough to do you a mischief.

The function of the GFCI is, of course, to detect that the high resistance path is there and remove power from the circuit thereby relieving the insurance company of the burden of having to pay out a benefit. The code requires GFCIs in certain locations for a good reason. It is written by the insurance companies.

 

[UndeadFred]

I have a GFCI on my system (in a "spa panel"). However, I have to agree that GFCI's are no substitute for adequate grounding. There can be situations with a lost ground that the GFCI then becomes completely worthless. But yes, if a hot shorts to the properly connected ground, or outside of the kettle, both sides, both hots are disconnected. For $50, that and having a big enough shutoff is worth it. But I often wonder if it gives an electric brewing system owner a false sense of security. I do know people who are much more careless with water and electricity because they think the GFCI will simply trip if they start to get hit with AC. True, but depending on how wet you are, it still could be too late.

I check my grounds about every other brew on my system, just in case. I would go out on a limb and say that IF you checked your grounding with a meter every time you used the system, you could safely get away without a GFCI. But in the grand scheme of things it's a cheap ($50) secondary insurance policy against stupidity. But the good ground still needs to be there for it to have a return path to trip.

 

[Owly055]

Check out the new thread I just started on GFCI failure rates......... and Google it yourself!

H.W.

 

[Owly055]

I have a GFCI on my system (in a "spa panel"). However, I have to agree that GFCI's are no substitute for adequate grounding. There can be situations with a lost ground that the GFCI then becomes completely worthless. But yes, if a hot shorts to the properly connected ground, or outside of the kettle, both sides, both hots are disconnected. For $50, that and having a big enough shutoff is worth it. But I often wonder if it gives an electric brewing system owner a false sense of security. I do know people who are much more careless with water and electricity because they think the GFCI will simply trip if they start to get hit with AC. True, but depending on how wet you are, it still could be too late.

I check my grounds about every other brew on my system, just in case. I would go out on a limb and say that IF you checked your grounding with a meter every time you used the system, you could safely get away without a GFCI. But in the grand scheme of things it's a cheap ($50) secondary insurance policy against stupidity. But the good ground still needs to be there for it to have a return path to trip.

Unfortunately it is NOT cheap insurance, it's a false sense of security. You should check your GFCI EVERY TIME......... Checking grounding is as simple as having a push button that routes a significant load through the ground from one leg. If the ground carries the load (120 volt load), it works, and will protect you. There are a number of clever ways to do this.

H.W.

 

[stevehaun]

I am not getting into this deliberation. However, IMHO, this is a very wise statement:

A person should always design something like a brew stand as if
GFCI didn't exist.

 

[passedpawn]

As another poster wrote "touche"................ I've worked with electronics all my life, and am well aware of how networks of resistors work. Most folks here are pretty ignorant about electricity, hence the oversimplification......The reality in this case is that the path to ground has virtually no resistance, where your body has very high resistance. 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. One resistor at essentially zero ohms, another at 229K ohms.......... 50 amps flowing to ground, how much current is going to flow through your body??? Essentially none. 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? 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.
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.
How many of your large appliances are on GFCI? 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. Even your refrigerator is usually not on GFCI, though 120 can kill you just as dead as 240.

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.

H.W.

That multimeter test isn't valid. Impedence goes down pretty fast as the the frequency increases - I'm not sure what it typically is at 60Hz. People do get electrocuted all the time so, regardless of what you think your multimeter is telling you, electrocution is a reality.

The "can't let go" current level at 60 Hz is about 15mArms - I imagine that's why the GFCI level is set at 5mA. So, ohms law, if the body impedence gets below 8kohms, you're a goner (at 120Vac). On split phase, both lines are 120V to gnd.

Like you said, grounding exposed metal is a given. If there is a direct short from L->N or L->GND, the breaker will trip. But if the fault is NOT a direct short, IOW if the fault does not exceed 30A (or whatever the breaker is), it'll just sit there patiently waiting for you. If a live ckt comes into contact with the wort, will the resistance of the wort allow 30A? Maybe, maybe not. Do you feel lucky today?

 

[GilaMinumBeer]

I'm completely rational, have been working with high voltage electricity for over 50 years including working in the field with centerpivot irrigation systems that run on 480 3 phase which have no such protection.

Now wait a minute here. In another thread you claimed to have been unemployed for 40 years, subsisting on 1-2 hours a day of public internet trading.

 

[Owly055]

Now wait a minute here. In another thread you claimed to have been unemployed for 40 years, subsisting on 1-2 hours a day of public internet trading.

I've been self employed for about 40 years. The last few of years I've been semi retired day trading in the stock market. I think I said I've not had a "job" for 40 years. That's not the same as "unemployed".

H.W.

 

[doug293cz]

in fairness to owly, code doesn't explicitly call for gfci protection for electric brewing systems. code calls out specific requirements for gfci protection and it is limited to 125 volts, 15 and 20 amp receptacles in specific locations. so if you are running a 240v system, code does not require gfci protection. applications that would require gfci protection by code would include 120v systems that are plugged into receptacles which require gfci protection (e.g. kitchen countertop, outdoors, garage, etc.) it doesn't matter if you are plugging in a brewing controller, appliance, power tool, whatever. the receptacle itself requires gfci protection so your brew controller will have the protection.

all this being said, code describes minimum requirements only. absolutely nothing wrong with adding gfci protection where it is not required. it is of course not a substitute for proper wire sizes, proper installation techniques, good electrical practices, etc. but man, it sure is some cheap insurance.

It's not surprising that code doesn't say anything about brewing systems. In the grand scheme of things, electric brewing systems are pretty rare compared to other household installations/appliances. If they were common, I'm pretty sure code would add something about them.

Does code really not say anything about spa installations requiring GFCI? I've never seen a spa that didn't use 240V.

Brew on

 

[Owly055]

I think you need to come back to "reality land"........ Remember what you've written here next time you are stirring a pot on your kitchen range, or loading wet clothes into your dryer. I'm imagining you running back and shutting off the circuit breaker every time you need to stir a pot, or touch the clothes drier. I sure hope you don't have copper pipe to your water heater!! Seems to me that you are dancing with death every single day....... or your wife and children are!!

Please explain to me the difference between stirring a pot on the stove...... which does not have a GFCI, and brewing.......... You depend entirely on good grounding on both the range and the drier...... How's that different from your brew stand?

H.W.

That multimeter test isn't valid. Impedence goes down pretty fast as the the frequency increases - I'm not sure what it typically is at 60Hz. People do get electrocuted all the time so, regardless of what you think your multimeter is telling you, electrocution is a reality.

The "can't let go" current level at 60 Hz is about 15mArms - I imagine that's why the GFCI level is set at 5mA. So, ohms law, if the body impedence gets below 8kohms, you're a goner (at 120Vac). On split phase, both lines are 120V to gnd.

Like you said, grounding exposed metal is a given. If there is a direct short from L->N or L->GND, the breaker will trip. But if the fault is NOT a direct short, IOW if the fault does not exceed 30A (or whatever the breaker is), it'll just sit there patiently waiting for you. If a live ckt comes into contact with the wort, will the resistance of the wort allow 30A? Maybe, maybe not. Do you feel lucky today?

 

[UndeadFred]

Unfortunately it is NOT cheap insurance, it's a false sense of security. You should check your GFCI EVERY TIME......... Checking grounding is as simple as having a push button that routes a significant load through the ground from one leg. If the ground carries the load (120 volt load), it works, and will protect you. There are a number of clever ways to do this.

H.W.

I actually said "secondary insurance". I don't think my comment contradicted anything you said or anything in your quoted reply above.

Having a trip circuit like that is a great idea. In a system like mine with the GFCI, the indication would be that the GFCI trips. I'll have to add that in the next iteration of the design. I'm about to RaspberryPi control my setup anyway, so the iteration will probably make it in after the next brew.

Interestingly enough, when I suggested this exact trip circuit as an emergency off (instead of a contactor) I was poo pooed in a major way on this very site. I don't use a contactor in my single kettle setup, I either hit the "test" button or flip the breaker to turn the system off. I'm still quite alive...

I should add that the TEST button on the GFCI only tests the GFCI itself, it does noting to verify the proper grounding in the system. It would only fail if the downstream ground (the input to the spa panel) was bad.

Fred

 

[itsnotrequired]

It's not surprising that code doesn't say anything about brewing systems. In the grand scheme of things, electric brewing systems are pretty rare compared to other household installations/appliances. If they were common, I'm pretty sure code would add something about them.

Does code really not say anything about spa installations requiring GFCI? I've never seen a spa that didn't use 240V.

Brew on

oh yes, not at all surprising it doesn't address brewing system. there is way to much electrical 'stuff' out there to address every possible scenario.

and code definitely addresses spa installations and similar 240v systems it is just that the most common locations where folks use brewing systems is in/around the the home. there are separate gfci requirements listed in the code for vending machines, carnivals/circuses, mobile/manufactured homes, recreational vehicles, floating buildings, temporary installations, pools/spas, fountains/ponds, marinas/boatyards and natural/artificial bodies of water.

most of these are areas where folks don't do any brewing but instances where 240v receptacles explicitly get called out include areas around bodies of water (within certain heights/distances). this includes lakes, pools, fountains, etc. but even these areas are limited to 20 amp circuits. around pools and boat hoists, any 240v stuff is on gfci whether it is hard wired or plug connected (for the most part, within certain distances).

one of the main reasons most of the gfci rules apply to receptacles is because that is where someone with a wet hand could get exposed to live electrical parts as they plug in/out equipment. and limited to 15/20 amp since this is the most common type of receptacle around where stuff is routinely plugged in/out. there just isn't that much 240v or 30+ amp stuff in wet areas where equipment is routinely plugged in/out so code doesn't bother addressing it.

hard-wired is a different animal in that under normal use, you just can't come into contact with live parts. that's why your electric oven/stove in your kitchen doesn't need gfci protection, even though most near everything else does. sure, you could get exposed to live parts if it malfunctioned but it is so uncommon, there isn't a need to have additional gfci requirements.

now compare this to an electric brewing system. most of them are plug connected, especially for mobile systems. folks unplug heating elements and/or pumps during the brewing process, often with wet hands. how is unplugging these items in potentially wet environments any different than in a kitchen, where the same loads would need gfci protection by code?

just seems smart to me to have gfci...

 

[passedpawn]

I think you need to come back to "reality land"........ Remember what you've written here next time you are stirring a pot on your kitchen range, or loading wet clothes into your dryer. I'm imagining you running back and shutting off the circuit breaker every time you need to stir a pot, or touch the clothes drier. I sure hope you don't have copper pipe to your water heater!! Seems to me that you are dancing with death every single day....... or your wife and children are!!

Please explain to me the difference between stirring a pot on the stove...... which does not have a GFCI, and brewing.......... You depend entirely on good grounding on both the range and the drier...... How's that different from your brew stand?

H.W.

Those are good points. However, on those devices it's hard to find access to any electrical circuit. I guess if you took a lopper to the heating coil you could. On our homemade brewing systems, I think there are a lot of opportunities for hand/water/electricity contact (not to mention many/most of these things are being built completely unqualified people who are trying to copy some schematic they found on some online forum). Pumps and liquid tubing everyone make it that much more hazardous.

BTW, my hot water heater is absolutely connected by (flexible) copper pipe to the copper supply lines that run throughout my house. I sweat the fittings myself when I installed it

 

[augiedoggy]

I think you need to come back to "reality land"........ Remember what you've written here next time you are stirring a pot on your kitchen range, or loading wet clothes into your dryer. I'm imagining you running back and shutting off the circuit breaker every time you need to stir a pot, or touch the clothes drier. I sure hope you don't have copper pipe to your water heater!! Seems to me that you are dancing with death every single day....... or your wife and children are!!

Please explain to me the difference between stirring a pot on the stove...... which does not have a GFCI, and brewing.......... You depend entirely on good grounding on both the range and the drier...... How's that different from your brew stand?

H.W.

For one thing electric stoves and dryers are not usually a DIY project made at home more times than not by an electrical amateur. Comparing them as such is wrong... and we both know that most home brewing applications have more potential for spills and "wet accidents due to pumps , valves and boilovers... thats why so many still brew in basements garages or outdoors even with electric..

Give it a few years and dryers and stoves will require them too...

 

[itsnotrequired]

Give it a few years and dryers and stoves will require them too...

its already happening, at least in locations other than dwelling units. 2017 nec added this requirement:

"all single-phase receptacles rated 150 volts to ground or less, 50 amperes or less and three-phase receptacles rated 150 volts to ground or less, 100 amperes or less installed in the following locations shall have ground-fault circuit-interrupter protection for personnel."

this applies to kitchens, bathrooms, garages, locations within 6' of sinks, etc. locations other than dwelling units would be businesses, schools, churches, etc. not there yet for dwelling units but you can see the writing on the wall...

also note the phrase 'single-phase receptacles rated 150 volts to ground or less'. your typical 120/240v single-phase system is 240v between hot legs but only 120v hot-to-ground so 120/240v systems would fall under this requirement (e.g. plug-in electric clothes dryer). also note this applies to receptacles with cord/plug connections only, not hard-wired.

 

[thekraken]

many/most of these things are being built completely unqualified people who are trying to copy some schematic they found on some online forum

It ain't the way I wanted it! I can handle things! I'm qualified! Not like everybody says... like dumb... I'm qualified and I want respect!

 

[ajdelange]

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.