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.)
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Grainfather s40 to 3 prong dryer outlet.
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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.)
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Woops, I was on a strafing run through the forum, didn't read carefully. Sorry all
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
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.
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.
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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.
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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....
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?
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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you can buy pre-assembled cords (assuming it is long enough):
https://www.amazon.com/Parkworld-886634-T-Blade-Receptacle-Adapter/dp/B07FHLZ9HS
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?
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.
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.
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.
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.
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 shits 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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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.
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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
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and to clarify, the reason they say not to use an adapter, is the round one is dedicated ground right?
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...
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!
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.They say not to use an adapter because of course they say that.
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They say not to use an adapter because of course they say that.
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.
The neutral wire on a NEMA 10-30 or 10-50 (10-50 is used for an electric range) is not a normal neutral. It has to originate in the service entrance panel, not a subpanel. So it makes a perfectly good and acceptable ground. The neutral wire from a subpanel is not safe to use as a ground. (unless it's a subpanel in an outbuilding that bonds the neutral again) Grainfather not knowing if a NEMA 10 is wired correctly is a little different than knowing if a NEMA 5 or 6 is correct; those can originate from a subpanel with no problems.
InspectorJon
Well-Known Member
Regarding GFCI:
It provides no over current protection. That’s what a circuit breaker is for. The circuit breaker protects the wire from over heating. GFCI protection protects people. It will trip with a very small amount of current going to the wrong place. Far less than will cause electrocution.
Now both kinds of protection can be found in one circuit breaker device so that kind of confuses some people. But GFCI protection and over current protection are different things, sometimes provided by separate devices and sometimes it’s all in one device.
i'm loosley familar with the difference between them, one protects the house, and is slow. the other protects you, and is really fast. GFCI is like a accountant that makes sure, every electron that goes out charged comes back uncharged....
i'm not sure why i couldn't find a 250v 20a GFCI plug though? the one with both hot & neutral sideways...just 120v 20a plugs with the single sideways pin?
as island lizard said, is it because 220v is ALWAYS shared neutral-ground at the box?
InspectorJon
Well-Known Member
240 volts can originate in a main panel or sub panel, if it is wired that way. Most sub panels have 240 volt capacity. Neutral and equipment grounding wires are handled differently in a sub panel than a main panel.
240 volt circuits do no use a neutral conductor but should always include an equipment ground. The old scenario where a dryer or range used the third wire in a 240 volt circuit to function as a neutral conductor was confusing and potentially dangerous, thus it is no longer allowed.
The equipment grounding system is one of the most confusing parts of the electrical code. In general practice it simply connects all the bare and green wires together and bonds them to the utility neutral in the main panel and the earth. It gets confusing when sub panels and separate structures are introduced. I’ve seen a lot of electricians and jurisdictional inspectors get it wrong in obscure situations. All the experts can’t even agree on some best practices.
I’m pretty sure we have gone a lot deeper than that OP though when he asked if a dryer plug could be used for the Grainfather. I think the answer is it could be used but it is clearly debatable whether it should be. One would have to investigate the wiring at the origination point to be sure the equipment grounding is correct. Then one must decide if they want to live by the letter or spirit of the law.
240 volt circuits do no use a neutral conductor but should always include an equipment ground. The old scenario where a dryer or range used the third wire in a 240 volt circuit to function as a neutral conductor was confusing and potentially dangerous, thus it is no longer allowed.
The equipment grounding system is one of the most confusing parts of the electrical code. In general practice it simply connects all the bare and green wires together and bonds them to the utility neutral in the main panel and the earth. It gets confusing when sub panels and separate structures are introduced. I’ve seen a lot of electricians and jurisdictional inspectors get it wrong in obscure situations. All the experts can’t even agree on some best practices.
I’m pretty sure we have gone a lot deeper than that OP though when he asked if a dryer plug could be used for the Grainfather. I think the answer is it could be used but it is clearly debatable whether it should be. One would have to investigate the wiring at the origination point to be sure the equipment grounding is correct. Then one must decide if they want to live by the letter or spirit of the law.
probably right.
(but i've learned a thing or two, and still kind confused...why do they sell 4 prong->3prong with the added ground wire to use...and not the 20a 250v plug to 3 prong with a similar ground wire to use?)
Perhaps because the overcurrent protection is wrong? (30A vs 20A) I don't know, but that is a plausible reason.probably right.
good point! but that would only effect the cord to the device right? so if I was rigging up an electric kettle, to plug into my dryer socket, just make sure to use wire rated for 30A?
edit: but then why would they sell them without the ground wire?
The cord to the device, and the device itself. (btw, the electrical code does not concern itself with cord-attached devices) I assume the GF will not be left running unattended for hours on end, so I would not worry about the breaker rating being 50% too high. If it starts to overheat, unplug it
I would use 12 gauge high temperature cable. In smaller sizes it's called HPN. In #12 it'll be some kind of SJ-something but I don't remember what.Edit: I have a 105°C cord on my heat stick. The markings on the jacket are hard to read, but it says SJEOW.
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so if just the cord going to the device isn't rated for 30A and the breaker at the box is...then something like this for the OP's question?
https://www.amazon.com/AC-WORKS-3-P...t=&hvlocphy=1013509&hvtargid=pla-888414843968
it's got a built in 20a breaker, i think, for the plug conversion? (but still no ground?)
https://www.amazon.com/AC-WORKS-3-P...t=&hvlocphy=1013509&hvtargid=pla-888414843968
it's got a built in 20a breaker, i think, for the plug conversion? (but still no ground?)
12 gauge high-temperature cable is rated for 30A, but not continuous 30A. (at least it used to be, and that's not the sort of thing that changes) But you're not drawing 30A, only at the most 20. Does the GF have a detachable cord? Or a wiring box for hard-wiring it? Make your own cord with #12 cable and a replacement NEMA 10-30P plug (they are cheap), then you won't need any adapters. Even better, buy a replacement dryer cord with a molded plug, but those cables are pretty big so make sure it will fit through the strain relief clamp.
LOL, man...that's what i was thinking..but thought it would be too complicated, and was trying to simplify.....still i'm just left more confused. that i'd have to convert the 20a 220v plug to four prong, then back to 3 prong to get the ground wire......
RufusBrewer
Well-Known Member
No I do not.
He may do what ever he want's to do. I just know that I wouldn't want a 30 A breaker "protecting" my $500 investment, a 15 A. rated appliance.
Cheers,
Joel B.
You plug your 100 watt lamp into your 15 amp circuit breaker.
I think the failure that circuit breakers protect equipment against is a short circuit. If my grainfather starts drawing 23 amps, I do not count on my 30 amp breaker to protect it. I am sure there are sections of the grainfather that would be damaged with 10 amps flowing through it.
@RufusBrewer You can do what ever feels OK & safe to you. Also read post #20, & 21 where I try to clarify my point. As I have said, I wouldn't.
Cheers,
Joel B.
Cheers,
Joel B.
InspectorJon
Well-Known Member
The first adapter you speak of is a listed device made for a specific purpose, to plug a new dryer into an old receptacle. In theory there are an unlimited number of adapters they could sell. What they do sell is limited by demand. They only make ones that there is a significant demand for. You could maybe make your own but it would not be a listed device. Listed means it was tested in a lab environment and they know how it will perform when used according to instructions. Unlisted does not specifically mean unsafe, it just means untested. An unlisted, homemade device may or may not be safe.probably right.
Some of the listed products are a bit disingenuous. The dryer adapter you speak of assumes you will connect the ground wire to an approved equipment grounding source, which is a properly sized wire that goes back to the equipment grounding system in the panel. That is part of its listing. Pretty much nobody is going to do that. If one did go to that trouble then they might as well just install a four prong receptacle and skip the adapter.
but then the dryer wouldn't work anymore!
Not sure if this is a joke or not. The dryer will work with a 3-wire or 4-wire cords; it doesn't care, and replacement cords are cheap. If you install a 4-wire cord on a dryer that use to be 3-wire, there should be a bonding screw or jumper wire or something that you have to remove in the wiring box. (it connects the neutral connection to the frame) HTH
Not sure if this is a joke or not. The dryer will work with a 3-wire or 4-wire cords; it doesn't care, and replacement cords are cheap. If you install a 4-wire cord on a dryer that use to be 3-wire, there should be a bonding screw or jumper wire or something that you have to remove in the wiring box. (it connects the neutral connection to the frame) HTH
but the dryer cord i learned, in my dryer epic. carries both 120v & 220v.....so the 3 prong GrainFather plug with the two sideways prongs, just carries 220v, with a ground also? i'm thinking, so if someone converted their dryer plug to the 6-20?..for the GF to plug into with proper ground...even if you swaped the plug on the dryer to match, it wouldn't work, would it?
The dryer needs a 10-30 (3-wire) or a 14-30 (4-wire) outlet to plug into. It could be adapted to plug into a 6-30, but that would be wrong, and why would you do that because 6-30 receptacles are more expensive than 10-30s. Its 120V requirement is just one side of the 240V to neutral. In a 3-wire dryer, it pretends the neutral wire is a ground and ties it to the frame. The 10-30 circuit anticipates this and has extra restrictions on its neutral wire (it has to originate at the service entrance panel, not just a subpanel unless that subpanel is also a service entrance (that would be weird but it can be done))
The Grainfather I assume wants a 6-20 receptacle, (2 hot wires and a ground, no neutral) so you need to derive one or replace the cord and plug. I don't know how many watts the GF draws, but probably less than 3840 because it has a 20 amp plug and being a resistive load you have to derate the plugs and cords 20%. (240V x 20A x 0.8)
Can you just run a new 240V 20A circuit with a NEMA 6-20 outlet? That would be the cleanest solution, and if you can do it yourself it might be cheaper than buying adapters. Use 12 gauge cable (or wire and conduit) and a 20A 2-pole breaker.
The Grainfather I assume wants a 6-20 receptacle, (2 hot wires and a ground, no neutral) so you need to derive one or replace the cord and plug. I don't know how many watts the GF draws, but probably less than 3840 because it has a 20 amp plug and being a resistive load you have to derate the plugs and cords 20%. (240V x 20A x 0.8)
Can you just run a new 240V 20A circuit with a NEMA 6-20 outlet? That would be the cleanest solution, and if you can do it yourself it might be cheaper than buying adapters. Use 12 gauge cable (or wire and conduit) and a 20A 2-pole breaker.
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either way if the 3 prong with sideways prongs and round one.....install a second plug with a box next to the dryer plug....good idea....and now i'm kinda making a joke but, why is it all the sudden people aren't recycling their electrons, and sending them back to the power company? and just dumping them in the ground? did california start this separate grounding stuff like CRV?
i mean i've apparently learned from this thread....i can run my 120-220v stuff with one wire, and just another stuck in the dirt?
A single wire ground return system is possible. I don't know why anyone would ever do that; I doubt that it's legal.
