Grainfather s40 to 3 prong dryer outlet.

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blkandrust

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I am interested in the GF S40. The S40 uses a nema 6-15 plug. What adapter would I need to plug the nema into a 3 prong dryer outlet? Thanks in advance.
 

doug293cz

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Most three wire dryer outlets are NEMA 10-30 receptacles. Thus you would need an adapter with a NEMA 10-30 plug on one end and a NEMA 6-15 receptacle on the other end.
NEMA 10-30.png

NEMA 6-15.png


Edited to include correct NEMA 6-15 drawing.

Brew on :mug:
 
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kartracer2

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@blkandrust First I'd like to make you aware that you dryer outlet is probably rated for 30 amps. You will need to replace the breaker (fuses?) to 15 amps because the cord & wiring of the GF are not rated for 30 A. A simple jumper cord set is not enough to be safe.
I am not aware of an "adapter" for your usage. You might have to buy a female cord end that mates to the end of your unit. You will also need a chunk of 12/3 rubber cord and a receptacle that matches the outlet. Wire accordingly. Another option is to replace the cord end on the GF to mate to the dryer outlet. (see above warning again)

Now I have a question for you, Will the dryer outlet need to remain usable for a dryer? If not you could replace the outlet and plug it in directly w/out any adapter setup. (same breaker swap will still be required)

Cheers, :mug:
Joel B.
 

kartracer2

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@blkandrust I stand corrected,

Same breaker change required for proper protection.

Cheers, :mug:
Joel B.
 

doug293cz

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@blkandrust First I'd like to make you aware that you dryer outlet is probably rated for 30 amps. You will need to replace the breaker (fuses?) to 15 amps because the cord & wiring of the GF are not rated for 30 A. A simple jumper cord set is not enough to be safe.
I am not aware of an "adapter" for your usage. You might have to buy a female cord end that mates to the end of your unit. You will also need a chunk of 12/3 rubber cord and a receptacle that matches the outlet. Wire accordingly. Another option is to replace the cord end on the GF to mate to the dryer outlet. (see above warning again)

Now I have a question for you, Will the dryer outlet need to remain usable for a dryer? If not you could replace the outlet and plug it in directly w/out any adapter setup. (same breaker swap will still be required)

Cheers, :mug:
Joel B.
Code doesn't require appliance cords to be rated for the same ampacity as the outlet for 15A and 20A 120V circuits. You can plug 16AWG cords into these outlets - you don't need 14AWG or 12AWG respectively. Code may require appliance cords to be rated differently for higher current, higher voltage circuits. Do you know if this is an actual requirement?

Brew on :mug:
 

doug293cz

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@blkandrust I stand corrected,

Same breaker change required for proper protection.

Cheers, :mug:
Joel B.
6-20 and 6-15 are not inter-mateable. OP says the plug is 6-15, and the adapter you link is 6-20.

Edit: Nevermind. The link says 6-20 receptacle, but it will accept either 6-15 or 6-20 plugs.

Brew on :mug:
 

doug293cz

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Breakers do not actually protect your appliances. They are there to protect the structure wiring from overheating if your appliance fails in a way that causes it to draw more current then it is supposed to (i.e. a short.) Breakers trigger when circuits are overloaded, either from connecting too many, or too large, loads to them, or loads (appliances) failing.

There is a small risk that your appliance could fail in a way that would draw more than 15A but less than 30A, so that the breaker won't trip. Unless the current draw is significantly more than 20A, your appliance cord will not heat up enough to cause trouble (unless you have it tightly coiled, buried in insulation, or some other strange condition) before you notice that your appliance has failed. If your appliance goes dead short, the 30A breaker will trip before your appliance cord can get hot enough to start a fire.
 

doug293cz

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it should be noted that the s40 instructions explicitly state not to use a nema 10-30r receptacle

View attachment 751081
The 10-30 is wired with a ground. Three wire dryers hijack the ground by using it for the 120V neutral as well as safety ground. Because of this, the frame of a dryer may be at a voltage slightly above ground, depending on wire run length and neutral current. My understanding is that code requires new construction to provide 4-wire outlets for dryers, so that neutral and ground are separated.

Probably the bigger issue is that a dryer with any 120V internal loads cannot run on a GFCI protected outlet. If you need to run both the dryer and the s40 on the same outlet, then you need to put an in-line GFCI in the adapter cord.

Brew on :mug:
 

Brewdog80

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You do not need to change a breaker. That is idiocy. You plug a 1 amp lamp into an outlet that is 15 or 20 amp rated every day. As long you don't plug a 30 amp appliance into a 20 amp breaker you are ok.
 

kartracer2

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Dear @blkandrust & others,
Please disregard my statements about changing your breaker. Looking back at those words I see that I was telling you it was required to do so. It is not required to do so. I should have just kept my keyboard quiet rather that expressing what I still stand by, an effort to better protect you investment. I am sorry for any angst these suggestions may have caused you or any body else.
I hope you enjoy your new GF and may it brew you many gallons of tasty beer.
Cheers, :mug:
Joel B.
 

Brewdog80

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It's a very common thought that it is needed when you are dealing with things like 240v wiring. I didn't meant come off harsh either. But wanted to insure the OP doesn't go out and spend $50 or more on a breaker and even possibly getting an electrician out when not needed. But you all be safe, even 120v kills.
 

kartracer2

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I have worked with 480 v 3ph and down to "low voltage", I was always taught that you fuse to the load while staying under the current carrying capacity of the associated wiring. That is why I made the statements I did.
Oh and by the way, it isn't the voltage so much as the current that will kill you, (see "Van De Graph generator").
Cheers, :mug:
Joel B.
 

doug293cz

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I have worked with 480 v 3ph and down to "low voltage", I was always taught that you fuse to the load while staying under the current carrying capacity of the associated wiring. That is why I made the statements I did.
Oh and by the way, it isn't the voltage so much as the current that will kill you, (see "Van De Graph generator").
Cheers, :mug:
Joel B.
Loads inherently self limit the current that can flow thru them. If they didn't, they would be shorts.

Normal practice is to wire loads with the smallest wire (within reason) that will carry the required load current (and still meet code requirements.) If following this practice, then fusing to the wire capacity also effectively fuses to the load.

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kartracer2

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So @doug293cz , you are saying in this case, the cord going to the GF is the fuse? When plugged in it becomes part of the circuit correct? Is 14 AWG (or what ever is used, certainly not #10 AWG) good for 30 A. in this case? #14 AWG will carry more than 30A. or try to ,,,for a while, then it starts to let the smoke out of it. I guess I don't understand why fusing closer to the rated amperage of the appliance is not a good thing.
Cheers, :mug:
Joel B.
 

doug293cz

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So @doug293cz , you are saying in this case, the cord going to the GF is the fuse? When plugged in it becomes part of the circuit correct? Is 14 AWG (or what ever is used, certainly not #10 AWG) good for 30 A. in this case? #14 AWG will carry more than 30A. or try to ,,,for a while, then it starts to let the smoke out of it. I guess I don't understand why fusing closer to the rated amperage of the appliance is not a good thing.
Cheers, :mug:
Joel B.
Not at all. Rated wire ampacities are very conservative. They are based on higher than room temp ambient, and in somewhat thermally insulated environments, with multiple wires running in close proximity. These represent worst case conditions.

14 AWG in open air can carry 30A indefinitely without "letting out the smoke". If the load shorts out, current will be much higher than 30A, but then the main breaker will trip within a matter of a few seconds (or less depending on degree of over current.)

14 AWG wire has a resistance of 0.0083 ohm/meter or 0.00253 ohm/ft. Since the current flows thru two wires the total resistance per foot is 0.00506 ohm/ft. At 30A the heat generated is 30A^2 * 0.00506 = 4.55 W/ft. This is slightly below the linear watt density of typical low power roof heating wires (5 W/ft.)

Here's a nice video about over current and wire heating. In the demo, he is using wire with a 1.0 mm2 cross section vs. 14 AWG wire which has a cross section of 2.08 mm2. So, his wire will have a resistance per foot 2.08 times 14 AWG wire, or 0.01053 ohm/ft (for both wires.) At 25A (about 5:25 into the video) the watt density is 25A^2 * 0.01053 = 6.58 W/ft, compared to 4.55 W/ft for 30A thru 14 AWG. So, at 30A the wire will warm up, but less than shown in the video.

Brew on :mug:
 

kartracer2

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14 AWG in open air can carry 30A indefinitely without "letting out the smoke".
Yes I know about free air, conduit, trough, tray etc wire current capacity differences. Wire insulation type changes things in various environments also. This situation is not that. We are talking cheap rubber cord and a molded cord end.
I would be willing to bet that if he hired an electrician to wire up that GF as a separate circuit, as it should actually be, he would not use #10 wire and a 30A breaker.
That is all.
Cheers, :mug:
Joel B.
 

doug293cz

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Yes I know about free air, conduit, trough, tray etc wire current capacity differences. Wire insulation type changes things in various environments also. This situation is not that. We are talking cheap rubber cord and a molded cord end.
I would be willing to bet that if he hired an electrician to wire up that GF as a separate circuit, as it should actually be, he would not use #10 wire and a 30A breaker.
That is all.
Cheers, :mug:
Joel B.
No, I wouldn't expect so either.

All I'm saying is that in the event of a dead short failure inside the GF, things are unlikely to go up in smoke before the fault is discovered. I think the most likely fail is an open in the heating element (and in that case, the fusing is moot), or failure in the control electronics (which is unlikely to cause an over current condition.)

Brew on :mug:
 

Brewski_59

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it should be noted that the s40 instructions explicitly state not to use a nema 10-30r receptacle

View attachment 751081
This is a very important consideration. No ground wire connection on this outlet can be dangerous. You CAN NOT utilize a neutral path for ground. As this can result in an unsafe condition. Since the center pin on the NEMA 10-30 is connected to neutral Its a bad idea to use an adapter that will allow your ground connection on the GF to be connected to neutral.
 

kartracer2

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Man I really hate to add my opinion on this subject again but I would imagine that with when that outlet was probably installed, the neutral and the ground are bonded at the panel. That would make the neutral a grounded conductor at that outlet in a round about way. That's the way things were done years ago.
Cheers, :mug:
Joel B.
 

Brewski_59

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Man I really hate to add my opinion on this subject again but I would imagine that with when that outlet was probably installed, the neutral and the ground are bonded at the panel. That would make the neutral a grounded conductor at that outlet in a round about way. That's the way things were done years ago.
Cheers, :mug:
Joel B.
I didn't want to get into this discussion again. BUT, while its true that inside the panel the neutral and ground busses are bonded together. This should never be done outside the panel. The issue is that all the neutral wires are designed to carry current, its part of the circuit. The ground is never enegized except when its doing its job to protect you from a fault. The danger here is that on the grainfather the ground is going to be bonded to the metal of the device. If its connected to a neutral, then there is the potential for current to flow from the neutral to the skin of the grainfather. This can result in the user getting a shock.
 

PCABrewing

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But you all be safe, even 120v kills.
In fact, I was told in electrical safety training that 120v kills more people than any other voltage.
This is because of the level of opportunity created by the huge installed base.
We were being educated about the hazards presented by the primary voltage of commercial electric service.
 

PCABrewing

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Man I really hate to add my opinion on this subject again but I would imagine that with when that outlet was probably installed, the neutral and the ground are bonded at the panel. That would make the neutral a grounded conductor at that outlet in a round about way. That's the way things were done years ago.
Cheers, :mug:
Joel B.
As far as I know, new construction still includes a ground stake near the service entrance that is connected to the neutral buss in the panel. I believe this is to minimize the potential for neutral to be floating above local ground.
That depends on the integrity of the ground stake and the outside connection. Could make for some interesting/scary behavior if the neutral of the service is ever broken.
 

InspectorJon

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Some thoughts...
The third bare or green conductor in old dryer circuit wiring goes to the equipment grounding bus in a main panel or a subpanel. It is perfectly safe to use as an equipment ground assuming it was wired correctly when installed. Old dyers used to use this grounding conductor as kind of a bootleg neutral but it was decided that this is not a good idea (and it isn't) and now we are required to have separate grounded (neutral) and equipment grounding conductors for appliances that use both 120 and 240 volts. Thus the new dryer receptacles have four holes. I don't know how the GF works but it is a strictly 240 volt appliance it should be fine to connect it to an old dryer circuit.

People plug very expensive electronic equipment into circuits that are rated for much higher amperage than needed every day. We plug computers that draw very little current and cost far more than the GF into 15 and 20 amp circuits all the time. The circuit breaker is intended to protect the wires in the wall and the rated receptacle connected to it, not the devices plugged into the receptacle.
 

Brewski_59

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@Brewski_59 I understand your point but I'm sure the dryer and probably electric range (if he has electric) uses this arrangement. (see photo). So the dryer is no more or less safe than his GF will be.
View attachment 751429
Again just my opinion.
Cheers, :mug:
Joel B.
Electrical safety is nothing to be cavalier about. I'd have serious concerns using a dryer plug since it doesn't provide a safe path to ground, There is no GFCI protection, and it is specifically warned against by the manufacturer. Just because the dryer is connected in such a manner, the argument that its as safe with the GF isn't valid. There is a large amount of water being used while brewing beer. Modern dryer plugs include a separate path to ground. This bonding to neutral is no longer allowed in the current NEC, yet there is a grandfather clause for existing equipment such as your picture. I'm just pointing out the obvious flaw in the logic of using an adapter that ties the GF ground to a neutral conductor. Here is a good article discussing the changes, and reasons for them. Neutral and Grounded
 

InspectorJon

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Electrical safety is nothing to be cavalier about. I'm just pointing out the obvious flaw in the logic of using an adapter that ties the GF ground to a neutral conductor.
I was making the point that there is no neutral conductor in an old dryer circuit, only an equipment grounding conductor. It does provide a safe path to ground. If the GF needs a neutral conductor it should not be connected to an old style dryer circuit and should have a four conductor cord end.


1638575963406.png

If the original dryer receptacle was wired properly the statement that it provides a hot-hot-neutral connection is incorrect, at least as far as my understanding of the old NEC and common wiring practices go. I do agree that one should always follow the equipment manufacturer's installation instructions.
 
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kartracer2

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Well I'm going to retire my dead horse beating stick. In the interest of safety and sanity for all involved, my new position is the OP should hire a qualified licensed electrician and have him run a dedicated (up to current code) circuit to where he want's to use his shinny new GF. Please disregard any and all advice/opinions I have expressed or implied (or may have been misconstrued as cavalier) previously.
To the OP @blkandrust I hope when you get to use your new GF it produces a great product for years to come.
May you all have a good day.
Cheers, :mug:
Joel B.
 

bracconiere

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Well I'm going to retire my dead horse beating stick. In the interest of safety and sanity for all involved, my new position is the OP should hire a qualified licensed electrician and have him run a dedicated (up to current code) circuit to where he want's to use his shinny new GF. Please disregard any and all advice/opinions I have expressed or implied (or may have been misconstrued as cavalier) previously.
To the OP @blkandrust I hope when you get to use your new GF it produces a great product for years to come.
May you all have a good day.
Cheers, :mug:
Joel B.

well i'm no electrician....but they don't sell a 3prong adaptrer, you can wire to ground rod? what i did in my ancient house when i had two prong plugs and was getting noise on my stereo....seemed to solve the problem....i'm not sure but something like this, with wire going to a copper, ground stake?


 

bracconiere

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i think that little dongle thing is meant to be stuck into a ground on a 120v plug now that i think about it.....should solve all the problems? maybe?
 

kartracer2

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i think that little dongle thing is meant to be stuck into a ground on a 120v plug now that i think about it.....should solve all the problems? maybe?
Naw,@bracconiere That cute adapter would be used to allow a newer dryer cord to be used in an older style outlet. You are right about the dongle thing though. The adapter I linked to in post #6 would be closer to what the "OP" needs or could use if all of humanity wasn't in the balance.🤫
But hey, never hurts to have another idea or thought bracc. You just keep on swinging, can't hit the ball if you don't swing the bat. (LOL)
Cheers, :mug:
Joel B.
 

SaltNeck

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If your dryer outlet is run off the main breaker panel then ground and neutral are bonded and you can use an appropriate adapter or cut the current plug off and wire in one that will work with the dryer outlet.

If your dryer is far away from the main breaker and there's a sub-panel in between then you'd want to get an outlet installed with the correct configuration. Since it would be a new outlet might as well get a four wire L1, L2, G, N configuration such as 14-30R and simply use the L1, L2, G of a 14-30P to wire your S40.

Instead of a GFCI breaker you can use a plug in GFCI or wire one in but they do add to the cost.

Post a picture of your dryer plug and your main breaker panel! It might even be a 10-50P (mine is!) in which case you would just need a GFCI.

30 Amp Inline GFCI (gfcistore.com)

If I'm speaking Greek to you or you don't like taking pictures then by all means hire an electrician.
 

bracconiere

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doug293cz

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This is a very important consideration. No ground wire connection on this outlet can be dangerous. You CAN NOT utilize a neutral path for ground. As this can result in an unsafe condition. Since the center pin on the NEMA 10-30 is connected to neutral Its a bad idea to use an adapter that will allow your ground connection on the GF to be connected to neutral.
Neutral wires, and ground wires both connect to the same place in the service panel (they are "bonded" in the service panel.) The only differences are:
  • In normal operation a ground should not carry any current, and a neutral is intended to carry current,
  • Neutral wires are supposed to be insulated, but ground wires can be bare.
If your application uses any 120V, then that current should flow thru the neutral, and not the ground (except in the case of a three wire dryer where ground is used for neutral. This is grandfathered for existing wiring, but not allowed for new wiring.)

The 240V Grainfather does not use any 120V internally, so it does not need a neutral to operate. Thus there is no problem using the grounded wire in the outlet as the official ground. You will have a safety ground

I didn't want to get into this discussion again. BUT, while its true that inside the panel the neutral and ground busses are bonded together. This should never be done outside the panel. The issue is that all the neutral wires are designed to carry current, its part of the circuit. The ground is never enegized except when its doing its job to protect you from a fault. The danger here is that on the grainfather the ground is going to be bonded to the metal of the device. If its connected to a neutral, then there is the potential for current to flow from the neutral to the skin of the grainfather. This can result in the user getting a shock.
The 240V Grainfather does not have any internal 120V loads, so there is no neutral current involved. Therefore there can be no current flow to the metal of the Grainfather, and no higher than ground potential on the grounded conductor (since there is no current flowing thru it in normal operation.)
Electrical safety is nothing to be cavalier about. I'd have serious concerns using a dryer plug since it doesn't provide a safe path to ground, There is no GFCI protection, and it is specifically warned against by the manufacturer. Just because the dryer is connected in such a manner, the argument that its as safe with the GF isn't valid. There is a large amount of water being used while brewing beer. Modern dryer plugs include a separate path to ground. This bonding to neutral is no longer allowed in the current NEC, yet there is a grandfather clause for existing equipment such as your picture. I'm just pointing out the obvious flaw in the logic of using an adapter that ties the GF ground to a neutral conductor. Here is a good article discussing the changes, and reasons for them. Neutral and Grounded
A three wire dryer plug does provide a safe path to ground, except perhaps when it is actually used for a dryer that has internal 120V loads. The real issue is that you will not have a GFCI breaker on a three wire dryer circuit (because the dryer will trip it every time it is turned on), so it needs to be added externally. I made the GFCI point earlier in this thread.

Brew on :mug:
 

InspectorJon

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don't sell a 3prong adaptrer, you can wire to ground rod?
All equipment grounding components should be bonded together. Driving a second ground rod and using it for equipment grounding is not allowed unless it is bonded to the rest of the equipment grounding system. It is possible to develop current potential between two separate grounding rods. The earth is not an approved or efficient conductor. It should not be depended on to carry enough current to trip a circuit breaker, which is the primary purpose of the equipment grounding system.
 
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