Supplying power -- 3-prong range outlet?

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This whole thread has become a personal attack on my ideas, knowlege and designs.

Done.

You shouldn't feel that way. You should stand your ground and defend your position and be willing to concede if you're wrong. I'm not saying you are but this is an argument you have an interest in. Don't give up man.
 
It's the existing wiring that is being grandfathered in & not the dryer or stove, and because so many houses are wired three wire the industry has to support the old standard with three range and dryer wire plugs.

That's true and so there is an exception for dryers and ranges but not for anything else.

Because of this it does not matter what's being plugged into the grandfathered wiring.

It does matter what is plugged in. Article 250.114 "Equipment connected by cord and plug" lists equipment which must be grounded. These are things like refrigerators, freezers, sump pumps, dish washers etc. Furthermore Article 250.142(B) says "Except as permitted by 250.30(A)(1) and 250.32(B), a grounded circuit conductor shall not be used for grounding non-current carrying metal parts of equipment on the load side of the service disconnecting means or the overcurrent devices for a separately derived system not having a main disconnecting means.

"Exception No. 1: The frames of ranges, wall-mounted cooking units and clothes dryers....

"Exception No.2: ...meter enclosures..."

This is also why it is perfectly legal (and safe) to plug you PROPERLY WIRED brew rig into a 3 wire 240V 30 Amp (dryer) or 50 Amp (range) outlet.

Referring to 250.114(4)(f) we find that "cord and plug connected appliances used in damp or wet locations or by persons standing on the ground or metal floors...." are required to be grounded. As one of these brew rigs is not a range, cooking unit, or clothes dryer it would not be legal to ground it with the neutral in an existing 3 wire H/H/N receptacle.

If you can argue that I have misquoted or misinterpreted these sections of the code or find other sections that exempt brew rigs then please site them instead of just saying that it's legal and safe without any supporting evidence.

An interesting twist here is that 250.114(4) pertains to 'other than residential occupancy'. There is no similar requirement in a residential setting (at least in the 2002 version of the code). Seems to me that's an obvious omission because there are damp locations in residences too but I don't write the code. We'll come back to this.

Article 250.118 says "The equipment grounding conductor run with or enclosing the circuit conductors shall be one or more or a combination of the following:
(1) A copper, aluminum...."

Note the key phase "conductor run with or enclosing the circuit conductors". That doesn't mean one of the circuit conductors. A circuit conductor (neutral) can only be used for grounding under the exceptions of 250.142(B).

If you ground your equipment using the neutral you are definitely illegal because you have violated 250.142(B). Again I encourage you to debate this point with supporting arguments rather than blind assertion that it is incorrect. However it seems that you could be legal if you did not ground the equipment at all as this type of equipment is not on the list of things that has to be grounded in a residential setting. Would you want to take this approach? In building such a system you are installing industrial type equipment in a damp location or at least one where liquids have the potential to be thrown about. The fact that you want GFCI protection reflects this. Given this I would think that you would want to consider the spirit of the code and realize that winning the argument is less important than saving your life.

Now why isn't it safe (or as safe as it could be) to use the neutral as the ground source? This has been explained by several people so it's probably a waste of typing to explain it again. In the event of an asymmetrical load or fault (such as contact between wort and one side of a heater) the potential of the neutral will rise above ground or it may already be above ground. In my house it is 100 mV above ground depending on what loads are on. One hundred mV is nothing to worry about when you are standing on a dry floor in rubber soled shoes and touch something connected to the neutral but under wet conditions, skin abrasion etc it could do you in. And of course we're not talking about the nominal offset, were talking about a fault situation where the potential difference is volts. Even so you would probably get away with it 999,999 times out of a million. A disaster is a coincidence of multiple events each of which is by itself very unlikely but given the obvious complexities of the code it should be clear that it there to protect you against these unlikely events.

And proper wiring for one of these outlets is to connect both ground and neutral to the third (white or outside braid) wire!
If you do that and then use the connected wire to ground kettles, your system box etc. you are very clearly in violation of 250.142(B). This has been explained to you before. The fact that you don't accept it either says you don't understand, don't wish to understand or understand but think you know better. I would be concerned about publishing advice which would cause readers to violate the code and do something which is potentially unsafe especially when it is so easy to do it right.

The Home Depot SPA panel is just a convenient way to add a GFCI breaker into the wiring for those who want one.

A spa panel is no more than a sub panel. It is equipped with separate neutral (insulated), and ground busses. They are not to be interconnected unless an isolating transformer of less than 1000 VA capacity is being used.
 
You shouldn't feel that way. You should stand your ground and defend your position and be willing to concede if you're wrong. I'm not saying you are but this is an argument you have an interest in. Don't give up man.

This thread has been taken to a level bordering some religious discussions I've witnessed. And I blame myself as much as any other contributor.

We can all continue to bash each other well into 2013 or go back to brewing beer.
 
Except that here the bible is based on sound engineering principles and decades of experience in fire prevention and safety enhancing techniques. Unlike the bible the code can be updated as the needs of the industry change and as new risks and technologies are discovered.

Also I must say I haven't seen any personal attacks (well maybe a couple of small ones). Apparently some consider questioning of their positions as personal attacks but picking up your marbles and stomping off the playground isn't a very mature attitude and is not one conducive to development of deeper understanding.

Someone complained that the code makes unreasonable demands on us when we build our own equipment. The code does not expect you to build your own equipment. It expects us to buy 'listed' equipment or equipment which has UL or other certifying laboratory seal of approval. Knowing that "The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity." I want any equipment I build to be as compliant with it as possible because there are reasons for all the provisions. This does put a heavy burden on me because the damn thing isn't exactly light reading. Grounding is a particularly difficult area because the reasons for the grounding rules aren't always obvious. As a consequence I've had professional electricians miswire panels in my house and I have also stumbled onto professional electricians' bulletin boards where essentially this same subject is debated with equal heat (and real personal attacks). Interesting.
 
Except that here the bible is based on sound engineering principles and decades of experience in fire prevention and safety enhancing techniques. Unlike the bible the code can be updated as the needs of the industry change and as new risks and technologies are discovered.

Also I must say I haven't seen any personal attacks (well maybe a couple of small ones). Apparently some consider questioning of their positions as personal attacks but picking up your marbles and stomping off the playground isn't a very mature attitude and is not one conducive to development of deeper understanding.

Someone complained that the code makes unreasonable demands on us when we build our own equipment. The code does not expect you to build your own equipment. It expects us to buy 'listed' equipment or equipment which has UL or other certifying laboratory seal of approval. Knowing that "The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity." I want any equipment I build to be as compliant with it as possible because there are reasons for all the provisions. This does put a heavy burden on me because the damn thing isn't exactly light reading. Grounding is a particularly difficult area because the reasons for the grounding rules aren't always obvious. As a consequence I've had professional electricians miswire panels in my house and I have also stumbled onto professional electricians' bulletin boards where essentially this same subject is debated with equal heat (and real personal attacks). Interesting.

I mostly agree with you - I was a practicing electrician for many years. I've seen my share of electrician screw-ups like floating grounds and reverse wiring (hot on white, neutral on black). But NEC does not expect you to buy any plug-in device to any code because the NEC covers wiring. The sentince you quoted "The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity." includes that 1930's antique electric fan you may have bought off eBay, or one of the 1920's - 1940's vacuum tube radio I restore, all of which use non-polarized plugs and have exposed metal parts, and all of which carry no modern UL certification.
 
Say the spa panel is mounted on the brew stand and connected to a pre-1996 50a range outlet (H-H-N). Is it possible/safe/legal to drive another grounding rod to connect the spa panel earth ground. You wouldn't be connecting the neutral and grounding wires at any point and you'd have a true 4 wire system for the spa panel.

It was mentioned earlier in the thread, but I don't remember reading a response to the idea.
 
I don't see how the NEC could possibly expect everyone to buy and read the NEC code book before they plug something in. It's just unrealistic and too far reaching IMO.

The NEC doesn't expect people, generally speaking, to buy and read the NEC code book. However, most people aren't wiring up spa panels and fabricating electric brew systems, et al. The average consumer is plugging in a lamp, or a TV, or a welder that they purchased as a complete, tested, and approved unit.

General consumer safety relies on engineers and manufacturers to adhere to sound practices guided by NEC and perhaps UL, and such devices passing the appropriate certification and approval criteria, so the average Joe doesn't have to be a Code expert. What's going on here is a completely different matter.

DEIT: Sorry...more or less a duplicate of AJ's post...
 
But NEC does not expect you to buy any plug-in device to any code because the NEC covers wiring. The sentince you quoted "The purpose of this Code is the practical safeguarding of persons and property from hazards arising from the use of electricity." includes that 1930's antique electric fan you may have bought off eBay, or one of the 1920's - 1940's vacuum tube radio I restore, all of which use non-polarized plugs and have exposed metal parts, and all of which carry no modern UL certification.

What's your point here...that we should continue to foster 1920's ways, despite the knowledge and insight gained in roughly the last 90 years?

You're right in the semantics sense that NEC doesn't expect you to buy any device to any given code, but that's not license to intentionally or unintentionally violate NEC when it has articles that specifically apply to cord and plug connected equipment. 250.114 is very clear in this statement and is pretty much proof positive that NEC doesn't stop at the receptacle or hard-wired installations.
 
What's your point here...that we should continue to foster 1920's ways, despite the knowledge and insight gained in roughly the last 90 years?

You're right in the semantics sense that NEC doesn't expect you to buy any device to any given code, but that's not license to intentionally or unintentionally violate NEC when it has articles that specifically apply to cord and plug connected equipment. 250.114 is very clear in this statement and is pretty much proof positive that NEC doesn't stop at the receptacle or hard-wired installations.

No, my real point is we need to stop nit-picking eack other's opinions.

If you understand electrical wiring and want to use the SPA panel then go ahead and wire it yourself. But if you are unsure you should hire an electrician.

Say the spa panel is mounted on the brew stand and connected to a pre-1996 50a range outlet (H-H-N). Is it possible/safe/legal to drive another grounding rod to connect the spa panel earth ground. You wouldn't be connecting the neutral and grounding wires at any point and you'd have a true 4 wire system for the spa panel.

It was mentioned earlier in the thread, but I don't remember reading a response to the idea.

Yes you can legally and safely run a separate ground wire to the SPA panel, and if you do, the new ground has to be completely isolated from the neutral wire coming in. But you need to look at your local code requirements for sub-panel grounding.
 
...
Yes you can legally and safely run a separate ground wire to the SPA panel, and if you do, the new ground has to be completely isolated from the neutral wire coming in. But you need to look at your local code requirements for sub-panel grounding.

Try this idea: The scene is a farm with a barn on the property. The electric power is set up and delivered to the house. Power to the barn is run on overhead wires delivering 120/240V. In every case, the power is delivered as a 3 wire system and ground at the barn is established at that service panel using a grounding rod.
 
Try this idea: The scene is a farm with a barn on the property. The electric power is set up and delivered to the house. Power to the barn is run on overhead wires delivering 120/240V. In every case, the power is delivered as a 3 wire system and ground at the barn is established at that service panel using a grounding rod.

...And how that ground is provided is determined by local code because they know the local ground conditions. For example, here in North Alabama the ground would be through two ground rods no closer than 4' apart.
 

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