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Grainfather s40 to 3 prong dryer outlet.

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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 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?


https://www.amazon.com/Prong-Dryer-...cphy=9030231&hvtargid=pla-1038131009452&psc=1
 
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?
 
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.
 
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.
 
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:
 
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.
 
Replace the dryer receptacle with a 4-wire receptacle. Bring in an earth ground from the nearest outlet or switch.
Not necessary. The receptacle already has an earth ground, as has been extensively discussed above. The 240V Grainfather does not require an neutral, as there is no internal use of 120V (also, as discussed above.)

Brew on :mug:
 
Not necessary. The receptacle already has an earth ground, as has been extensively discussed above. The 240V Grainfather does not require an neutral, as there is no internal use of 120V (also, as discussed above.)

Brew on :mug:

Woops, I was on a strafing run through the forum, didn't read carefully. Sorry all :)
 
" A swing and a miss" (LOL) The 4 conductor plug is not in play at all @bracconiere .
Cheers,
Joel B.


hey now! my idea was the 3 sideways prong one to four prong, then plug the four prong adpater from the sideways three prong into the 4 to 3 prong adapter and stick the add on ground dongle into a ground socket! because i read post #30, that said it was just the lack of ground that made a 3 prong dryer socket unsuitable....

so it was like plugging the GF into a whatever to a 4 prong, then the 4prong plug goes in the OTHER adapter with the three prong plug and ground wire?

so it'd go from sideways, to 4...then back to 3 diagonal? lol :mug:
 
You can safely use the grounded wire of a NEMA 10 receptacle as either an equipment ground or a neutral wire, but not both* except for a few specific and listed cases like an electric dryer or kitchen stove frame. It is an insulated full-sized conductor that goes all the way back to neutral bar in the panel where the neutral and ground are interconnected. (that's why you can't have a NEMA 10 in a mobile home; the neutral is not bonded in a mobile home it is bonded in the external disconnect that supplies the mobile home)

I am not an electrician, so take my advice for what it's worth :)

*both would be where you had a 240V load and also a 120V load, like a 240V heating element and a 120V light or timer, so the grounded wire is slightly unbalanced but you still try to use it for a safety ground.
 
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:

my comment was more related to using a piece of equipment in accordance with manufacturer's instructions, a core concept of electrical codes. technically it only applies to listed equipment and i'm not sure the grainfather is listed but is still good practice.

that being said, the risk with using the 10-30r is minimal. there are no 120v loads so shouldn't have any current flow on the "ground" conductor under normal conditions. if the receptacle doesn't need to be used as a dryer, might not be a bad idea to move the neutral connection of the circuit at the panel from the neutral bus to the ground bus and add some green tape to it. electrically this doesn't make a difference but looks more "official". it still wouldn't be 100% kosher as the 10-30 configuration by definition has that third leg as a neutral, not a ground. again, practically, totally safe but may look strange to someone else looking at it.
 
It COMES with an ungrounded plug. two lines and the neutral. Just make up a short cord for adapter. ZERO issues, unlike the totally ignorant hack suggested for the Anvil foundry to use a 120 female plug to 220 male for the dryer or other 220 outlet(as it comes wired for 120v only.) some folks don't like following manufacturer instructions that say cut it off if you use 220v. I can just see someone plugging 120v item into that hacked cord....
 
being that i haven't been completly laughed out of this thread yet...what about something like this, make your own adapter? @kartracer2 would have to say where the 220v on the three prong male equivelent, wire yourself plug would be....

https://www.zoro.com/hubbell-wiring...vkaxzYmk-2YmAAAfDYw7gEBMHAXC1UcBoCEAMQAvD_BwE

so wire that thing up with a wire going to ground, for ground, and then 220v hot, and neutral...to what ever pins those are on the wire it yourself old style dryer plug....and get how ever long of cord you need that can handle the current?

and this on the other end....

https://www.amazon.com/L6-30P-Anti-...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl
i know i don't know proper cord gauge, but you'd get 220v...and being the plug is 30a, and the GF is a 15-20a unit, it's not going to heat up the wires right?
 
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being that i haven't been completly laughed out of this thread yet...what about something like this, make your own adapter? @kartracer2 would have to say where the 220v on the three prong male equivelent, wire yourself plug would be....

https://www.zoro.com/hubbell-wiring...vkaxzYmk-2YmAAAfDYw7gEBMHAXC1UcBoCEAMQAvD_BwE

so wire that thing up with a wire going to ground, for ground, and then 220v hot, and neutral...to what ever pins those are on the wire it yourself old style dryer plug....and get how ever long of cord you need that can handle the current?

and this on the other end....

https://www.amazon.com/L6-30P-Anti-...uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl
i know i don't know proper cord gauge, but you'd get 220v...and being the plug is 30a, and the GF is a 15-20a unit, it's not going to heat up the wires right?

you can buy pre-assembled cords (assuming it is long enough):

https://www.amazon.com/Parkworld-886634-T-Blade-Receptacle-Adapter/dp/B07FHLZ9HS
1639154430442.png
 


that was said in post 3, 6 or something....but the GF says it's unsuitable because it doesn't have ground....or dedicated ground? so you need to bassicly design the same thing as that, but like the 4 prong to 3 prong one with the extra wire for a dedicated ground? why i thought converting to 4 prong then back to three prong that had the ground wire would work? i've scoured the google sphere, and don't see a similar option for that type of converter cable?

edit: but if you built your own cable with the plugs that let you wire them up yourself, you could add a dedicated ground wire from the sideways 3 prong plug? then just ignore 120v on the 3 prong dryer socket?
 
How many wires does the GF have, and does it require 120V or 240V? You have everything you need available in a NEMA 30-10, *except* if you need both 120V and 240V and also need a ground. (and that seems very unlikely)

Nevermind, IslandLizard just answered my question. The ground wire on a NEMA 10 is insulated because they know it will be used as a neutral on certain listed equipment. Otherwise they'd just use NEMA 6 connectors.
 
that was said in post 3, 6 or something....but the GF says it's unsuitable because it doesn't have ground....or dedicated ground? so you need to bassicly design the same thing as that, but like the 4 prong to 3 prong one with the extra wire for a dedicated ground? why i thought converting to 4 prong then back to three prong that had the ground wire would work? i've scoured the google sphere, and don't see a similar option for that type of converter cable?

edit: but if you built your own cable with the plugs that let you wire them up yourself, you could add a dedicated ground wire from the sideways 3 prong plug? then just ignore 120v on the 3 prong dryer socket?

the whole issue here is one of nomenclature or definitions, not if it will actually work or be unsafe. by standard, a nema 10-30 is two hots and a neutral. using it in another manner technically wouldn't meet standard. that is why the s40 instructions say not to use a 10-30 since the existing circuit is setup as a neutral and will now be functioning as a ground. it is not unsafe for this particular application but grainfather as a matter of liability has to say not to use it.
 
There IS a dedicated ground, the top, L-shaped prong!
However, there is no dedicated neutral. And you don't need one on a 240V GrainFather.


so it just dumps all the used electrons that 'cooled' off to the dirt? which is why it doesn't work with a GFCI? no accountant?

edit: i would think it doesn't matter if a bear ***** in the woods or you train it to use a toilet....it's gotta relieve itself somewhere and if the toilet is preferable, but if you it needs a realive a really big load, that's what ground is for? so you need a dedicated wire for that ocasion?

edit #2: and even on low amp, low voltage it steady's the flow?
 
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It COMES with an ungrounded plug. two lines and the neutral. Just make up a short cord for adapter. ZERO issues, unlike the totally ignorant hack suggested for the Anvil foundry to use a 120 female plug to 220 male for the dryer or other 220 outlet(as it comes wired for 120v only.) some folks don't like following manufacturer instructions that say cut it off if you use 220v. I can just see someone plugging 120v item into that hacked cord....
No, the device comes with a grounded plug (NEMA 6-15), so there can be no 120V loads in the device. The discussion is centered around the "L" blade of of the 10-30 plug being "defined" as neutral, even tho it is functionally either a ground or neutral (and in a dryer is used as both.)

You cannot plug a 120V device into a 240V outlet, as the blade/slot spacing is different. Compare the 5-15 (120V) and 6-15 (240V) plugs/receptacles below.

NEMA 5-15.png

NEMA 6-15.png


Brew on :mug:
 
No, the device comes with a grounded plug (NEMA 6-15), so there can be no 120V loads in the device. The discussion is centered around the "L" blade of of the 10-30 plug being "defined" as neutral, even tho it is functionally either a ground or neutral (and in a dryer is used as both.)

You cannot plug a 120V device into a 240V outlet, as the blade/slot spacing is different. Compare the 5-15 (120V) and 6-15 (240V) plugs/receptacles below.

View attachment 751833
View attachment 751834

Brew on :mug:


and to clarify, the reason they say not to use an adapter, is the round one is dedicated ground right?
 
so it just dumps all the used electrons that 'cooled' off to the dirt? which is why it doesn't work with a GFCI? no accountant?
Basically, yes!

In both older and new code the ground prong is connected to the ground wire or wires/mantle in heavier wiring.

In the older code the Ground also functions as a Neutral, in the main panel Neutral and Ground are on the same bar. And yeah, connected to both a ground rod, and the mantle of the cable that's going to the meter, and from there on to the transformer on the pole or in the yard.

In the new code the neutral has it's own conductor and prong on the plug and receptacle. But ultimately, they both also get wired together in the panel, just as above in the older code.

So you tell me, does that toilet make a real difference...
 
So you tell me, does that toilet make a real difference...


i've used toilets that have some impressive flushing/sucking action!

(so for the cord between the two plugs that are wired by the user i posted....something like this as the cord then?

https://www.gfcistore.com/30-amp-inline-gfcis.html
)? $200 is spendy, but we're talking safety?

and @blkandrust i'm not just blowing smoke, or hopefully not ;), i've thought of using my 3 prong dryer outlet myself for brewing....this is all interesting....trying to figure out how i'd do it now myself!
 
and to clarify, the reason they say not to use an adapter, is the round one is dedicated ground right?

They say not to use an adapter because of course they say that. ;) They don't know that the adapter is wired correctly, or that the outlet it is being plugged into is wired correctly. That doesn't mean it is unsafe if you do it right.
 
They say not to use an adapter because of course they say that. ;) They don't know that the adapter is wired correctly, or that the outlet it is being plugged into is wired correctly. That doesn't mean it is unsafe if you do it right.
They also don't know if you plug it into a NEMA 6-15 receptacle, that the 6-15R is wired correctly (comes with a 6-15 plug in case you didn't remember.) Same thing applies to any appliance plugged into any receptacle. Liability for an adapter lies with the manufacturer of the adapter.

Brew on :mug:
 
They say not to use an adapter because of course they say that. ;) They don't know that the adapter is wired correctly, or that the outlet it is being plugged into is wired correctly. That doesn't mean it is unsafe if you do it right.

grainfather doesn't have issues with using adapters per se, this is why they show all the possible receptacle configurations you can plug it into using adapters. but all the ones they show as okay have two hots and at least one ground. 10-30 is the odd duck without a ground, at least as defined by standards. but as we have established, okay to use as a ground, simply grainfather not wanting to be on the hook if someone crosses neutrals and grounds and creates confusion.
 

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