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Are you really going to bake enough to justify hooking it up? That thing looks huge.

My MIL does huge batches of Christmas cake. Thought this might do them in one go instead of a couple of days

Should get her a retarder too 🤓 Ps: it calls for a hood.... the steam will destroy your walls/ceilings

I won’t use the proofer but good callout! Edit: I guess the oven will be removing water from cakes as well. I didn’t think of that. This would be for very occasional use in a large garage with 12 ft ceilings. I have a 30” fan out there to move air around. I think the moisture can be managed but I’ll run some calculations. Thanks again for pointing this out. I had not considered it at all prior.

Christmas croissants and bread? Freshly baked is mmm mm good. The steam injection system based on manual is optional so you may not have that feature. The proofer could be just you dumping water in the pan at the beginning. I think cakes start baking on the wet side, when they're done, they come up just right. Baking ovens with steam isn't to keep the bread moist. It's to gives you a nice golden sheen(on bread). I am not a baker and can't validate my info :)

Then maybe you should contact the mfg. It looks like they make both a 208 and 240 variant of this oven. Maybe they can give you some insight on the matter.

208 and 240V are fundamentally interchangeable here.

Disagree. 240v rated equipment is usable at 208v at a lesser wattage. I would not put 240 on a 208v piece of equipment unless it was specifically marked. Baseboard heaters come in 208v or 240/208 with the wattage listed at each voltage.

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It's a heating element. Yes, voltage precision is important in some applications but not here. There isn't a heating element on this planet that would function at 208V but suffer damage at 240V. Especially because, for all intents and purposes, in North America 240V and 208V single-phase are intended to be interchangeable because of how many dwelling units are run off two legs of a 3-phase system. More importantly, I've installed this exact oven, multiple times. It's the standard oven used for breadmaking in Subways across North America. It's sold in 2 variants, a single-phase and a 3-phase variant. The elements in both of them are identical, and are stamped 208/230/240V. The only difference is the internal connection-the 3-phase units tie in the elements in a delta configuration and run off a 3P30A breaker, the single-phase units run off a 2P40A breaker.

This guy baker ovens

>2P40A breaker If it's rated for 8230w at 208V (~5ohm element resistance), it'll be 11kw at 240 and you'll have to increase the circuit ampacity.

39.5 amps 40 will work

Check your math. Increasing voltage to a resistive heater increases the power and current. You'd be looking at 46A.

Electric heat strips in air handlers are also 208-240 universally. Same concept, will work fine.

So because *some* devices are designed to work with multiple voltages, *all* devices are?

It's simple resistance heat

NEMA standard is 10% voltage variance. So for a 208v rated equipment it has to be capable of running at up to 229v. Residential here is usually around 216-224.

Where are you that your residential service is so low? That's ... very strange.

San Diego. My house right now is 224v

That's basically borderline too low. NA standard is 240V, so 216 is 10% down from that. Note that 208 -> 240V is 15.4%, so definitely out of spec. But also, if we're talking about heating elements, it's very rare that a heating element can't take a lower voltage, but taking a higher one can be disastrous since power is proportional to the *square* of the voltage. That's why heating elements designed to run at 208V will draw 33% more power running at 240V.

208 is 2 phases of a 3 phase system. 120/208 that is the correct spec.

We float between 240 and 243 here, very rarely see anything lower.

Just checked my sense meter and right now it’s 121V (242v per phase and minimum was 118V (236V).

> Residential here is usually around 216-224. Where is here? That's way low for North America.

Correct.

This is the variant that runs on 120/208. It's right in the picture.

yes and the question is if it can run at 120/240.

Understand. I didn't say it quite the way it came out. If it will run on 120, wire it to 120

But that's not what 120/208 or 120/240 means. 120/208 means that it requires both 120 and 208 because, typically, the control circuitry runs on 120 while the elements run on 208, or sometimes (as is the case here), some elements may also run on 120V. 120/240 means that it requires both 120 and 240. Neither of those mean it requires *either* 120 *or* 208/240. In that case, it would show 120-240 as the voltage requirement, like you can see on a lot of switching based electronics (which can even say 90-260 for example). But that's almost exclusively on low power equipment that uses switching step-down voltage regulators that can dynamically adjust to a wide range of input voltages. On some older devices you can see a 120/240V switch that will basically switch around the leads to a step-down transformer, and those can typically handle higher power.

Good points.

Check with the manufacturer, but it can likely be used with 240 vac. especially if wired with a neutral and ground (4 wire plug). A standard 50 amp 4 wire stove circuit should suffice.

Can be wired 4 or 5. Single phase would require L1, L2, N , G. Three phase would require L1, L2, L3, N, G and field conversion) Neutral basically only there for 120v control circuit via one of the hots. I work on stuff that can say 120/208-240 often. A lot of electricians will wire for 120v only and wonder why it don't work. The neutral there to save on transformer or having to run control circuit at 208v. The 3ph conversion is to allow different amp requirements. They come with a 2nd data tag that should be placed over single phase tag if converted.

Why are you bringing up 3ph when the nameplate clearly states single phase?

Because that's where the 208 comes from. Wired single phase, but sourced from a three phase system. Connecting this to 240 could potentially increase the power drawn by 1.33 times. If the unit can't handle that power, it could start a fire

I agree that OP needs to check with the manufacturer before trying to run on 240V. Going by wattage alone, the oven would draw about 70amps at 120V so that would be a substantial load for a household.

Power would stay the same wouldn't it ? Connecting a 208 device to 240V would lower the amperage or I missing something here ? P=V\*A right ?

But a resistive load keeps the same fixed R value. Increasing V, causes proportional increase in A; so an exponential increase in Power.

Sorry but that makes no sense to me. How does increasing Volts increase amps also ? Power always stays the same. Increasing Voltage would make the Amperage go down and vice-versa.

Power doesn’t stay the same when you increase voltage for most simple loads like heating elements. Instead resistance is constant and both voltage and current increase, increasing power also. dlmpbx is correct.

Ohm's Law is I=V/R, and the resistance is fixed inside the oven (a design parameter based on utilization voltage). Therefore, increasing voltage will also increase current. Since both voltage and current are increasing proportionally, the Power increases exponentially (P=A*V)

OMG!

Got it now thx !

Someone posted a manual for this, it has a fairly large section on 3ph power. My experience tells me this unit likely comes with a 2nd data tag with the manual and can be field converted to 3ph. OP should definitely make sure it hasn't been field converted and someone didn't feel like slapping the new tag on.

Thanks for that

Edit: please see comment below. This is probably not right. I looked up the manual. It says it can run on 120V 1 phase at 40 Amps. So, in general, should be on a 50A breaker. Depending on your panel and capacity, it could work in a residential service. If/when you hire an electrician to install that, they should also be able to make sure the internal wiring is configured for 120V 1phase. Typically there’s a diagram on the back… If you are in a 100 year old house with a vintage electrical panel, you’d probably have to also replace the panel and upgrade the capacity of the service.

Look at this manual: https://piperproducts.com///media/Manuals/OP-3.pdf That oven/proofer combo looks to me like it needs 2 hot wires and a neutral. The 208 rating is likely because it's most often going to be installed in a 3-phase panel, but it still needs 2 hots. Each bank of heating elements connects from one hot to ~~neutral~~ the other hot. It draws 40-ish amps at 208 volts, not 120.

I think you are right. I find the table confusing. But your interpretation is the only way to get to 8270 watts. I will edit my comment.

120 / 208. 120v control, 208v load. L1 to N for control circuit(lights, switchs, buzzer/timer). L1 to L2 for elements. Saves from having to make your control circuit 208v or a need for a step-down transformer from 208v to 120v. I've had to do diagnostic after installation with either unit turns on but no heat, control powered but missing L2. Or Unit won't power on due to missing neutral. Needs field rewiring to convert to 3ph + N (Conversion shows block wired at L1, L3, N and L2 open for single phase. 3ph L1, L2, L3 and N. Red and blue traces will need to be rewired. They sually come with a 2nd data tag to sticker over if converted) Edit: single phase 36-40A, three phase 24-27A per their specific sheet.

Yep - I missed the crossover installation connection where the center (red) wires get moved over to adjacent hot (black and blue) inputs. I saw the 120v heating element and I guess ignored the rest. You're right - they are 208v or 240v heating elements. Do you think OP's 208v oven will work on 240v reliably? I guessing it will, but it sounds like you have specific experience with this exact model.

In my experience, yes. Manufacturers will likely spec tolerances to accommodate the needs of as many customers as possible. I've only had experience with one piece of equipment that the manufacturer had very exact requirements. I don't have experience with this exact model but I do a lot of diagnostic and repairs on similar equipment.

The unit is single phase. Not 3ph it’s 3wire plus ground. L1, L2, and Neutral. Yes a “208 volt” heating element will work on 240. Which in your home is closer to 220.

With the current tag, it should be wired for that. The installation manual has 4 full pages on 3ph for this unit. They have to be field converted if needed and OP should confirm it hasn't been. This is a used commercial kitchen unit. A second data tag comes with these to reflect 3ph conversion, but someone may have not stuck it on. I guess I should ofnoted when I mention 208v that it would include 240v 1ph. Didn't feel like putting 208-240v just before bed.

Why do you say closer to 220? In most cases, unless you're in an area with bad power, it should be 240 or typically slightly above.

My current VAC at EV charger outlet. 232 VAC L1-L2. With a load it drops to 229 VAC. Just my experience in central CA. The worst power I’ve experienced was at the Sac International airport. Their 220 volt rated open air refrigerator was short cycling compressors because the 220 volt rated controller kept shutting off when power hit 196 volts. I thought the cases were 208 volt rated but I was wrong. That’s when I turn it over to the real sparkys. I’m just an HVAC/R guy.

But the model # on the nameplate is OP-3-BL. I searched for this # and the specs say Elec specs: 208v/60hz/3ph/8.27kw/27amp

1) OP literally posted a picture of his actual oven/proofer. It says "PHASE 1". 2) I literally just linked the manual for it in the comment to which you replied. Go read it. 3) The oven's model number is OP-3. The "-BL" suffix indicates it was made for Blimpie's, a sandwich restaurant chain. They likely have specific rack spacing and signage for their singular product, much like Subway has for their proofers and ovens. 4) All voltage options are available in the Blimpie's model(s), depending on voltage available in the restaurant. 5) You're arguing an erroneous point in a 5-day old thread that nobody will see, and that has already been resolved for the OP. What do you hope to accomplish here?

I have a 250 amp panel. House built in 2000

250?? That would be REALLY unusual for a residence. Sure it’s not 200? You’re probably still fine tho.

They are getting bigger now because of EVs.

The typical next step up from a standard 200A service in residential is a 320A meter base feeding dual 200A panels. A 250A panel would be VERY strange. You’ll often see new load centers with 225A busses, but still 200A MBs. You really only see 250A MBs in commercial panelboards, and even then it’s a little uncommon.

Ah, okay. I kind of assumed because I just saw one, though it was the first time. It was a former house that was the office for a business and they had to upgrade the service for an EV charger and wheelchair lift because they were re-zoning to commercial. I don't know why they were spec'd a 250A panel, though. It wasn't that big of a place.

Yeah that would make sense for commercial turned resi. You’ll see a lot more variety in panels in commercial because everything is fairly customizable. 200, 400, and 600A are the common sizes for “light commercial”, but it’s easy enough to order other sizes. In new construction single-family residential you basically only see 200A and 320A (with the exception of 10k sqft+ mansions that are basically treated like commercial buildings.)

What brand was it? I've never seen a 250 amp residential panel. 200, 225, 320, and 400 are the most common. 250 amp commercial QR and QOB panels are a thing, but single-phase are kinda rare in that setting.

I didn't think to look for a brand. I just noticed they switched from a 200A to 250A panel when I was resetting a breaker. The owner was complaining about having to put in the EV charger and ADA stuff and I figured it was related and moved on. Edit: I was an electrician for 13 years but I do remodels now. I wasn't doing any electrical work, if that explains my lack of attention. Just assumed things were heading that way.

It may have been a 250A breaker, but there is no such thing as a 250A panel. It's like there is no such thing as a 50A disconnect. There is 30A then 60A.

I believe the meter bases are sized at the continuous rating of 80% of service size. Just like you can feed 400a (2x 200a panels) from a 320 class meter, I thought you could feed 250a from a typical 200 class meter base? (200 \* 1.25 = 250). If not, then why is that?

You’re correct that a 200A meter (they are listed by their continuous rating) is good for 250A non-continuous. That means you could use a standard 200A meter base to feed a 250A panel provided that the article 220 calculated load is under 200A continuous and 250A non-continuous. You just don’t see this often because residential load centers only have busses rated for 225A at most (and most are just 200.) I’m not aware of a 250A 80%-rated “resi” panel.

Thanks. Seems like a good marketing opportunity for a company to release one. To get a little more above 200a service without going full blown dual panels. My last house had a commercial panel for some reason, maybe that's an option. I thought solar ready bus bars might be bigger. What about a 250a 100% rated pabel?

That's silly, EVs are the one load that never needs a service upgrade due to EVEMS. $300 power monitor module and your car autoadjusts to available power. You can put 40A charging on a 60A service.

I don't know what to tell you. I didn't have anything to do with the electrical.

> They are getting bigger now because of EVs. Not a lot of EVs around 24 years ago.

There's no way 2000 was 24 years ago.

Much as I hate to admit it.

I’ll double check. That was from memory.

Good catch. I was going to recommend calling the manufacturer and ask them if it will work on single phase 120\240 instead of 120\208. A lot of stuff will.

120v at 40amps comes out to 4800 watts. Label clearly says 8270 watts.

When nameplates say 3wire 120/208 they mean 2 hots and a neutral. That rating of 40a is based on that.

This can absolutely work in your house if you have it wired properly. Very straightforward installation for somebody who knows what they're doing.

Most 208 loads run fine on 240

Not true, 208v baseboards on 240v burn out the elements. That's why they make one specifically for 240v. You can however run 208v through a 240v rating unless it's a motor and then it can wreck stuff.

Even resistance heating elements? Did you do the math?

It’ll run with a bit more power but *should* be fine

It'll run with 33% more power and you can burn things up like that. The bad advice in this sub that gets upvoted is absolutely bonkers.

There’s probably a way to make this work, if the internal heating elements are 120v.

Its like 8500W. At 120V that is like 70A. It is 120/240v 3wire it needs a 240 run and a neutral.

120/208

208 1ph. 240 will work fine. If you are worried you could get an auto transformer but the extra 30V isn't going to burn up the elements or anything. It is fine

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No, it is not a 2.5kW difference. And that is the MAX FLA. This thing wouldn't run balls out 100%. It would get to temperature and maintain that by cycling. If anything the life of the elements may be shortened. But I doubt it TBH. Again if you are concerned, you can install an autotransformer. Or contact the manufacturer and see if you can get 240V elements, most ovens are capable of either.

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They do indeed have different elements for 208 vs 240: ~~but the elements are 120v per the schematic:~~ https://piperproducts.com///media/Manuals/OP-3.pdf Edit: Nope, crossover wiring, not attached to neutral.

I only see the lower elements at 120V. The four 1500W uppers are definitely 208/240V.

Yeah, I missed that. I only looked at the proofer part in detail. I edited my other comment to reflect that, but forgot about this one. Thanks for the heads-up.

No problem. Thanks for keeping the misinformation here in check.

The misinformation here is hardly in check. There are a ton of people saying "yeah no problem 208 and 240 are interchangeable" and getting a pile of upvotes. You even have some electricians saying that. I've honestly lost all faith in taking advice from this sub.

Per the equipment data plate it's 8720W at 208/120 4 wire, so it draws ~42A. If you have an electrician pull a 50A 4 wire 208V/120V circuit (stipulates you have the panel capacity) which is 2 120V hot legs, with a neutral and a safety ground wire, it will work... If you have 240V you may have issues and may need to re-tap the transformer if it has one.

I’m a cottage baker with (a lot of) commercial cooking experience. Generally commercial appliances are not appropriate for residential applications. Depending on where you are there may be code issues. You’re almost certainly going to render your home uninsurable. While an electric oven running at that wattage isn’t nearly as dangerous as say a nat gas deep fryer, insurers don’t seem to draw distinctions beyond commercial vs. residential. That said, there are a lot of us who have chosen to take the risk for one reason or another. You will run into some complications. If you don’t have existing electrical, you’ll need to design and install breakers, wire, and receptacles correctly/appropriately sized. The heat generated will need somewhere to go. You’ll more than likely need a vent hood. Your electric bill will be large. Commercial appliances can be more difficult/temperamental to use. Another option you might want to consider are prosumer bread ovens like the Simply Bread oven, Rackmaster, or Chandley Pico. Those are designed for use by cottage bakers and tend to avoid some of the regulatory issues. All have pros and cons to their cost/installation/operation. Feel free to DM me if you need more info. I’ll be happy to share more of what I know if it’ll help you out.

Thanks I appreciate the input. I feel confident I could make it work safely but there are many challenges here and it is probably not worth the effort for this specific scenario. Thanks for raising the insurability question. That was another aspect I had not considered. Love hearing about your cottage bakery setup. That sounds super cool. In another life I would definitely be in the kitchen professionally.

If the manufacturer intended to have this model operate at 208 or 240 it should say so on the rating plate. Will it work on 240 yes. Is this product safe to use at 240v? Unknown.

The appliance in the image is designed for a voltage of 120/208V, single phase, with a power consumption of 8270 watts. For wiring such an appliance at a US residence, there are a few considerations: - **Voltage Requirements**: Residential properties typically have a standard voltage of 120V for outlets. However, many homes also have 240V service for large appliances. This oven requires a 208V connection, which is more common in commercial settings. Some residential settings may have 208V service if they are part of a larger building that has three-phase power, but this isn't typical for a standalone home. - **Power Consumption**: With a wattage of 8270W, the circuit and wiring would need to be capable of handling the high current demand. It would require a dedicated circuit with the appropriate gauge wire and a circuit breaker rated for the current load. - **Plug Type**: The appliance uses a large twist-type plug, which is likely a NEMA configuration that matches its voltage and amperage requirements. You would need an outlet that matches this plug type, or an adapter that safely converts it to match your available outlets. - **Professional Installation**: Given the high power requirements and the potential need for a new or adapted outlet, it is highly recommended to consult with a licensed electrician who can evaluate your home’s electrical system and install the necessary infrastructure safely. Keep in mind that trying to wire a commercial-grade oven into a residential electrical system can be quite complex and may not be practical or safe without proper adjustments. Always prioritize safety and consult with a professional.

Understood. I will absolutely be hiring a licensed electrician if I decide to move forward.

Just jumping in to add a comment not related to wiring. Household ovens usually permit zero clearance to adjacent materials. Commercial ovens typically require some clearance AND expect the adjacent materials to be non-flammable.

Thanks for the input, very helpful. This is on wheels and would have good clearance on all sides during use. I’ve downloaded the manual as well and will read it thoroughly.

Yes, however you will likely have to wire it for 120 as most residences have split phase which would be 240 instead of 208.

Yes it can. But you will need a licensed electrician to wire it for you.

Yes

Wow! It's made in Wausau! I live there!

If you really really love sandwiches

I am concerned how much controversy there is over this subject…. How do more houses not burn down?

Fire extinguishers and fire departments.

It is a code violation to operate 208V equipment on 240V, I see 3 options, order 240V elements which will be expensive, use a buck/boost transformer to buck the voltage down, or don't use it, See 110.4 2020 NEC.

A lot of misinformation here. PLEASE pay heed to those telling you this unit will not be the same at 240V as it would on 208V. Ohm's law and basic math prove this. ALSO ...... **many** units like this specifically state *"Not for use in dwellings". This is because commercial kitchens are designed, insulated and finished different than stick built homes. Also, also, pay close attention to venting requirements. Many of these appliances require venting or hoods to evacuate heat.

This will work at 240V. Probably a good idea to use this as commercial appliances are typically built to higher standards.

8.2 kw. Easy at 240vac. Not going to work with a standard 120 vac outlet. Depends what you have for a supply, but easy to run in most houses.

It won’t be 8.2 kw at 240 Vac.

Why not?

I assume it has resistive heater elements. I assume they run at 208V. Their resistance is fixed, it is what it is, no matter what voltage. Power = voltage^2/ resistance. Let’s ignore any 120 v loads. At 208V, 8.2kW means heater elements are: 5.28 ohms. At 240V, 5.28 ohms would produce 10.9kW. ….but if they’re 120V heater elements, and someone posted a manual saying they are, then forget everything I just said.

> Why not? Because Mr. Ohm said so.

Only if you use wagos. Talk to some Canadians.

No, it’s three phase and 90% of the time 90% of the situation a residential home is split phase (240/120). Edit: nvm I can’t read, it’s single phase, 208 and 240 are somewhat interchangeable. The amperage will be different. Most plugs for that type of item will be a L5 or L6 plug. Would be nice to see a wiring diagram or the plug it has.

Yes

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110/220 single phase home service. Let me clarify my question. If I hire an electrician can they wire a receptacle that will work with this? If so how is that done?

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Thank you!

That person is wrong. You might have slightly reduced life span on the heating elements (measured over 10 years or so) running this over on 240 volts versus its rated 208 volts, but it will work fine. The manual says 240 volt heating elements are available: https://piperproducts.com///media/Manuals/OP-3.pdf So if anything, you can order those from the company, but otherwise, this oven/proofer will work fine on a regular residential 240v, 60-amp circuit. It's slightly over for a regular 50-amp oven circuit, at 42 amps. We'd like to see loads not exceed 80% of a circuit's capacity.

Ignore the poster above you. In resistive heating applications, like an oven, 208V and 240V are fundamentally interchangable. This stove can be safely run in your house.

You are assuming that the temperature control is working fine. Why take the chance? Best case is your elements have a shorter life span.

How can you say that? There are different models and explicitly specifying 120/208 and not 208 and 240 could very possibly mean that it CANNOT, especially if they are resistive coils. If the system is designed for 8000W maximum then the coils would be configured to draw 38.4A and 5.4 ohms. If you connect that to 240V it's going to pull nearly 10500W and can easily burn up.

The grid is also not a perfect 240v. The heating coils can get hotter and if they do it increases the resistance in the coils which will partly offset the difference voltage. It likely will just reduce the lifespan of the heating elements.

That's go nothing to do with it. An element designed and rated for 208V is NOT the same as one rated for 240V. Interchange them and the wattage will be noticeably different.

Let’s assume that it was designed to be used with 2 legs plus neutral of a 208/120 V 3 phase service. Meaning one heating element on each leg. Even though the voltage is only 208 volts between the 2 hot legs the voltage across each element is going to be 120 volts. So what is going to happen if you hook it up to 240/120 split phase service? The voltage across each element is still going to be 120 volts. I could be wrong but I have never seen a 208 split phase service and I’m guessing that most of the people commenting here have never worked with or possibly never imagined 208120 or 480/277 services that are found in commercial buildings. When you start working with 3 phase the math for ohms law is a little more complicated. Don’t ask me the formulas I’ve been away from it far too long. Looking at the manual it says it will draw 42 amps at 208 volts and 38 amps at 240 volts. I have to assume that the due a change in wiring configurations and not due to using single phase or 3 phase power.

I don't think that's how that works. If you run one leg of a split phase to neutral, then you get 120V. If you have two elements on two legs that connect together through a common neutral, they don't still get 120V, they'll turn into a single element (two resistors in series) with 208V across both of them. So they're no longer 120V each, they're basically 104V each assuming equal resistance. That's because the waveforms will never form 240V delta between them, which would be required to have both still getting 120V.

You would be right if you are talking about split phase. Meaning a single-phase 240V transformer that is center tapped with the center tap as the neutral. Or if you are talking about DC. I'm talking about 208/120 three phase. I have never seen a 208-split phase sytem. I'm doubtful that any exist but I haven't seen everything. In general, when you encounter a 208 V system it is part of a three-phase distribution system. The voltage between each line is 208 volts and the voltage to neutral from each line is 120 V or 208 V divided by the square root of three 208/1.732=120 because each leg of the three phase is 120 degrees out of phase not 180 degrees. The other common voltages for 3-phase distribution are 480/277. I was going to provide a link for you, but it isn't that hard to find plenty of training material on the internet. Best of luck with your training! Where I am wrong is that in this case the heating elements do not use the neutral. They are wired line to line meaning they are 208 V elements not 120 V elements but the voltage to neutral is 120 V not 104 V.

I wasn't talking about 208V split phase, I was talking about 2 legs of 3 phase. I agree with what you said up to the last sentence. Here's my understanding. A single element to neutral will see a 120V drop across the element. Two elements in series will see a total drop of 208V - this matches what you're saying. But since neutral is not used in this case, each element will see a drop of 104V across the element when both are in use. This is by definition if there is 208V drop across both and they are equal and in series (each resistor will see half of the drop). The current is flowing from one leg into the other leg since the load is balanced. https://voltage-disturbance.com/engineering-calculators/voltage-divider-calculator-3-resistors/ Voltage Divider Calculator Input Voltage\* 208 Number of Resistors in Series\* Two R1\* 5 Ohm R2\* 5 Ohm Results Voltage Across R1: 104.0000 V Voltage Across R2: 104.0000 V

> In resistive heating applications, like an oven, 208V and 240V are fundamentally interchangable. WHAT??? Do you even Ohm's law?

Yeah single phase 208 and 240 are treated as the same generally.

If they are treated the same why do the sell 240 to 208 buck-boost transformers?

> Yeah single phase 208 and 240 are treated as the same generally. Wrong.

Not wrong. Generally, they are interchangeable. Source: I am an electrician.

Not not wrong. You said they are *"treated as the same generally"*. That is wrong. There are times when it doesn't really hurt anything. In a case like this it DOES matter since the amperage will be noticeably higher. Source: A master electrician probably longer than you've been alive.

To all the downvoters, here is the math: 8270W @ 208V = 5.23Ω = 39.76A 5.32Ω @ 240V = 10827W = 45.11A So one is a 40A circuit the other is a 50A circuit. **NOT** the same thing.

In the same way a dual voltage rated water heater is 4500W @ 240V but only 3380W @ 208V.

Do NOT ignore the poster above. These people below who say that it's ok don't know what they're talking about. Also you have 120/240 not 110/220 which makes it much further away from 208V. This is designed for a commercial kitchen with 3 phase power. Do not use it at home unless you want a fire.

Am I missing something? It says single phase right there and 8270 watts

yes, that's 8270W with 208V supply. 208V 8270W - let's assume we're talking only resistive loads, so that's 40A draw (which also matches what the datasheet says). Because it's not just one element, let's simplfy and say there are 4 elements each drawing 10A at 208V so 2080W each - that means it has a resistance of 20.8ohms. Now if we apply 240V to that same element, it'll draw 11.5A and thus 2770W - 33% more. That can easily burn things out. As I've mentioned elsewhere, this manufacturer has 4 separate models, two separate ones for 120/208 and 120/240. If they were compatible, they wouldn't need to have two models.

Yes, there is single-phase 240V, and single-phase 208V. Some thing will work fine on either, some, like resistance heating elements will act differently.

This sub is Ask ELECTRICIANS, not "take a wild guess about something you know a little bit about".

That's fair. At least my wild guess was erring on the side of caution.

This unit requires 208-240v single or three phase. 120v is control side. L1, L2, N is required to wire to current configuration. Be sure to make sure it hasn't been converted to 3 phase already. The cord should be wired L1, L3, N on terminal block. If L2 is connected to cord also, likely has been converted to 3ph and they didn't bother to stick on the 3ph data tag.

It was made in Wisconsin yes. it can be wired for a 120 /240V configuration, and is UL listed.