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Comment by PaulHoule | Hacker News Reader

We are thinking of switching some gas appliances to electric in our old farmhouse but we probably need to rework our electrical panel completely to add high amperage services for an induction range (my wife won't accept an ordinary electric range) and an electric water heater.

Fortunately our son is in training as a handyman and that means we can get him working on projects of all kinds around the farm. Of all the trades, electricity is the one that I know enough about to supervise somebody. (e.g. I am baffled by plumbing)

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If you need to upgrade your service entrance, if it's within your means, go to 400A to future proof (EVs, HVAC and hot water heat pumps, induction stove, and other large loads all add up, along with colocated generation of some sort). Depending on your authority having jurisdiction (AHJ) and utility, they may require a licensed electrician to replace the raceway or similar entrance to the meter. 200A is satisfactory if greater amperage isn't available (US centric advice). Think of this as the residential version of "dig once" [1].

EDIT: Yes, you may not need 400A immediately, but if you're doing an upgrade, the cost delta between the conductors for 200A vs 400A is not substantial except for very long runs. Also, some utilities will cover the cost of a service upgrade to the meter; from the meter onward into the home is your cost. Balance cost with future needs, future labor costs, etc. Very similar to dropping a whole bunch of cheap fiber in a trench just in case you need it in the future.

I usually recommend people combine this work with a solar PV install, to capture the 30% federal tax credit towards the work (if you can justify the upgrade as necessary, which you can if your current service is less than 200A), as it has no limit on the amount you can capture as part of the install (versus the previous tax credit for electrical upgrade costs for installing an EV charging station).

[1] https://www.fhwa.dot.gov/policy/otps/policy_brief_dig_once.p...

This is double-great advice. It's completely obvious once mentioned but not something that may have occurred of the top of ones head. Thank-you for posting.

It's strange because 400a service will probably NOT ever be needed, but the cost difference from 100-200 and 100-400 is basically nothing.

You can also get a separate meter installed instead or alongside, this can be useful it the property could be dual purpose (think: duplex, house + machine shop, etc). This can increase costs because of double baseline but it can also reduce costs because of double "low tier" - depends on the market.

I always forget the size difference between US and UK homes (I assume toomuchtodo is speaking from a US perspective). Here, in my three-bedroom UK house I'm on a 60A service fuse and considering updating to 100A in the future (amusingly, as part of a solar PV / electric vehicle charger install).

I've never heard of a UK house having a larger than 100A service (although I imagine they exist here and there - it's certainly not common).

I'd never heard of a 400 A service until just this discussion (it's common to have 100 A - 200 A), but it's important to keep in mind the voltage differences and that effect on total power:

UK: 100 A x 230 V = 23,00 W

US: 200 A x 120 V = 24,00 W

Edit: I am wrong in my understanding of US power distribution. It's 200 A per leg, which the US has two of. But it seems like the UK may or may not have 380 3 Phase, so the numbers are weird there too. Wrong all around!

Voltage to residential main electrical service panels in the United States is 240V. Major appliances run on 240V circuits.

So when you install a 400A panel in the US, it's 400A*240V which is 96,000W.

And service in EU is 380V, so the relationship between the numbers remains similar.

That is incorrect. The EU/UK are on 230V at 50Hz at residential service entry.

I'm not sure where in EU you live, but every instant water heater, stove, and many semi-professional workshop devices require 380V. At least in Germany, 380V is standard for such devices and available in every household.

3 phase vs single phase depends on which country you're in in the EU.

I think you might almost understand how it feels when someone makes gross generalizations across the entire US :).

One thing I keep learning about the EU is ... do not generalize using Germany as the baseline. There are many areas where Germany is the odd one out, not the standard.

Services to the US are at 240V though they just utilize a center tap transformer to allow two different 120v legs. So that 200 amp service is 200 amps at 240V so approximately 48kW. Largely US homes have bigger feeds in because the US has significantly larger homes on average and the prevalence of AC and other higher power usage devices in US homes.

> but it's important to keep in mind the voltage differences and that effect on total power:

> UK: 100 A x 230 V = 23,00 W

> US: 200 A x 120 V = 24,00 W

That's incorrect. The service drop in the US is 220V. It gets stepped down at the main load center to 120V for most of the regular circuits. So it's more like 48000W service in US houses.

The service drop in EU/UK is 380V. The point stands.

So that 380V would be for 3 phase to a home which is not always the case. There are plenty of homes in Europe that only have single phase to the house which is at 230V.

That is incorrect. The EU/UK are on 230V at 50Hz at residential service entry. The point does not stand.

This varies.

Houses and apartments in Denmark have 3 phase service. My apartment's main breaker is labelled 40A @ 380V.

I believe the oven and hob make use of it, but I haven't looked myself.

400V between phases, 230V phase to neutral. Most homes have single phase though.

So how would you run an instant water heater or electric induction stove then? Every apartment and house I've ever lived in had 380V three-phase right to the kitchen, to the bathroom, and to basement rooms (e.g. for prosumer workshop tools).

> So how would you run an instant water heater or electric induction stove then? Every apartment and house I've ever lived in had 380V three-phase right to the kitchen,

I run an induction stove on 220V single phase every day here in the US.

Isn't it two phase? AFAIK in the US you have 240V two phase with 180° between them.

The US uses a single, split phase

https://en.wikipedia.org/wiki/Split-phase_electric_power

We don't run an instant water heater. It's all gas or electric boilers.

For the stove I wired one phase to all the burners and the oven. It had one, two or three phase options. They're on a separate circuit with a 16 amp fuse. It's 2200W I believe. The breaker has never tripped.

400V is just not very common for residential in the Eastern Europe, maybe in your country you have instant electric heaters and other powerful appliances. My dad has recently upgraded his house to 400V 3 phase though, although he didn't need it but it's nice to have.

Only small correction to that is that load center doesn't step down voltage. The center tapped transformer at the street steps down the voltage to 240V, but then that center tap on the transformer becomes your neutral so you end up with two legs that are 120V from ground/neutral and 240V from leg to leg in your load center.

Thanks for that correction. In retrospect it makes sense, because each circuit breaker isn't functioning as a little transformer.

> The service drop in the US is 220V.

240V. Since we're throwing around numbers, let's be accurate. This is a pet peeve of mine. We've been standardized at 240V since 1967, and it was higher than 220V years before that.

Thanks for the correction about the actual voltage today.

However, it seems like 220V was the standard before that [1], which is why it's still common parlance, referring to the "higher" voltage. Certainly I've heard many people in the trades still refer to it with the older term, even if the circuit is actually 240V.

1. https://en.wikipedia.org/wiki/Mains_electricity#History

The voltage started at 220 way before the 60s, and then increased incrementally over the years, until standardizing at 240V. I don't know when the first bump past 220 happened exactly, and it may not have been simultaneous in all areas. I gather the reason for the standardization was to stop the creep and pick a voltage to stick with for everyone.

No, he's right.

It's not about having 400 amps per se but about sizing the wire you put in the ground. Maybe you'll have a 200a main breaker and you'll only ever use 200 amps, etc. - but the hard part was digging and future you or other future yous will be happy that the wire was upsized when it was put in.

Same with conduit. Same with number of conduits.

I can't tell you how many times I have been very pleased with myself that I threw in that extra 3/4 conduit line when we dug that one trench that one time ...

Isn't this because the UK standard is 230 volts? The US is only 120, so you need almost twice the amps for the same power.

Services to the US are at 240V they just utilize a center tap transformer to allow two different 120v legs. So that 200 amp service is 200 amps at 240V so approximately 48kW.

UK homes run on 230 volts, so each amp is worth double what US amps are worth (running on 115 volts in the US) edit: 115 volts per leg, and US has 2 legs, so it comes out in the wash, surprisingly. UK homes have tiny little service amps!

No. US homes run on 240V, not 120, and not 115 * 2. We provide a center-tap neutral so you can split the single phase 240V if you desire. And we do exactly that for many smaller circuits, including the majority of wall sockets.

A friend of mine has 400A of service in the UK in the countryside as it's an old farmhouse and is pretty large even by USA standards.

> if it's within your means, go to 400A to future proof (EVs, HVAC and hot water heat pumps, induction stove, and other large loads all add up, along with colocated generation of some sort

I have all of these on 200A with amps to spare. But I have a small house. I suppose if I had multiple EVs, dryers, or heat pumps, or 3000sqft it would be a different story.

Again, see above - it's not about 400 amps per se ... it's about putting in bigger wire because we can't predict the future.

It's spending a small additional amount now (on wire) to avoid an enormous expense (trench digging) in the future.

Oh, and you know that 3" conduit required for the 400amp ? Make it 4".

Oh, and you know that trench you just dug ? Throw in double 1.5" and double 3/4 conduits right in there with it.

Oh and you know that first two feet of dirt you filled in ? Now throw two more 3/4 conduits on top of that because you never know when a common carrier on that same pole will have fiber up on it ...

Future you will be very happy you did.

> Future you will be very happy you did.

The future could also look like large batteries on-site that charge slowly, and then provide power at high amperage when needed, like slowly compressing a spring, then suddenly releasing it.

This is already what Electrify America and Freewire (https://freewiretech.com/) are doing with EV Fast chargers when the electric utility can't provide a higher power connection in a reasonable time-frame. As battery prices drop, that could be a viable way to power heavy home appliances.

Good advice. I just did the 400 amp upgrade. Our 3200 sq ft house was still on 150 amp service from the 1980s, and going to 200 amps just didn’t seem to add much capacity relative to the cost. Was about $12K to go to 400 amps with two 200 amp panels.

> my wife won't accept an ordinary electric range

She's right. Induction has the speed and response of a gas cooktop with the precision a resistance electric cooktop.

> and an electric water heater.

Make sure it's a heat pump water heater if efficiency and operating cost matter to you.

> She's right. Induction has the speed and response of a gas cooktop with the precision a resistance electric cooktop.

This, and also easier cleanability than either of them (basically it doesn't need more cleaning than the rest of your kitchen counter) and much safer (won't heat anything non-metallic that you leave on top, won't heat the surface of the stovetop itself except indirectly via heat transmission from the pots/pans, and will automatically turn off if it doesn't detect a metallic item).

I have one and there's no way in hell I'd go back to an ordinary electric range as long as I can afford not to.

I've been looking at them, but almost all have unusable touch controls. (My background is human machine interaction - I've never seen an acceptable stove, but induction stoves are all really bad). Since I've have to replace all my cookware as well I'm not in any hurry.

Functionally, the touch controls make the whole thing much easier to clean, but I agree they are harder to use.

As with the touchscreens in cars, I'm sure it's also about marketing a sleeker product and lowering the bill of materials and labor - hence cost of manufacturing.

Just wait a little longer and a manufacturer will start offering physical dials on an induction stove as a high-end feature, but also realize that it will still be control by wire like a computer input device, not a mechanically coupled control like a (dumb) dimmer switch - since it would be ultimately controlling the inductor in the stovetop via software.

I've got an electric radiant cooktop. It has a number of those features such as easy to clean (just a flat glass panel) and won't heat without detecting a pan and will turn off the element if the pan is removed for more than a couple of seconds. It does get hot itself instead of just heating the pan, but when cooking I don't know that would make much of a difference. You've still got a very hot pan sitting on the cooktop imparting a lot of heat for probably a while.

Don't get me wrong there's other pros/cons to induction but you don't need to get induction to have those benefits.

The fact that induction cooktops don't get hot themselves make them even easier to clean. I had a flat glass electric cooktop as well in the past, it was of course much easier to clean than older ones with protruding stoves, but still, some liquids and sauces got stuck to it due to being hot and I had to scrub with a scouring pad or, in the worst case, use a scraper blade. This doesn't happen with induction so 99% of the time, cleaning the induction cooktop just boils down to wiping with a wet microfiber cloth. The scouring pad is seldom needed and I think I've used the scraper once or twice in eight years of having induction. On the other hand, the fact that the surface is less hot also means that you have to wait less to clean it.

I had no idea that some non-induction cooktops could also detect pans, though. In my mind that feature has always been linked to induction. Good to know it's not necessarily like that.

Precision makes no sense for a pan and is something a person who doesn't actually cook would care about. Your pans change temperature when cold food is put into them. Anyone who cooks knows that you are changing the temperature on your cooking surface constantly in many applications and it's based on the visual and audio queues your food give you. At no point have I thought "OK, I need to be at 400 degrees and in 1 minute I will adjust down to 300 degrees.". I don't care about precision like I would when doing sous-vide cooking or baking, for example - both of which are great uses for electric fuel sources.

The problem with induction is the thing it's good at (heating water quickly) isn't a useful feature. A gas flame is a 3D cooking surface and this is important as I want heat applied to the sides of pans in many instances. Also, copper and aluminium cookware don't work on them and they are superior materials for cooking with in many instances.

> Precision makes no sense for a pan and is something a person who doesn't actually cook would care about. Your pans change temperature when cold food is put into them. Anyone who cooks knows that you are changing the temperature on your cooking surface constantly in many applications and it's based on the visual and audio queues your food give you.

I know exactly what to expect when I set my induction stove to 8 (out of 10) and let my daily-use pan heat for 1 minute. That's the setting at which I can temper oil with dry spices without burning them.

This isn't a function of the induction element, but rather the digital controls. Naturally I adjust the setting once the cold food goes in the pan, but having a calibrated starting point for my cooking flow is pretty useful, and I cook for my family daily.

> The problem with induction is the thing it's good at (heating water quickly) isn't a useful feature.

An induction stove can heat anything quickly, not just water. And importantly it can rapidly change temperature, unlike a resistance electric stove.

> Also, copper and aluminium cookware don't work on them and they are superior materials for cooking with in many instances.

You can just use one of these:

https://www.inductioncooked.com/how-to-use-non-induction-coo...

However, I've never seen a recipe that called for a copper or aluminum pan specifically. The benefit of copper is supposed to be precision temperature control, but as you said, precise temperatures don't matter for day to day cooking.

> I know exactly what to expect when I set my induction stove to 8 (out of 10) and let my daily-use pan heat for 1 minute. That's the setting at which I can temper oil with dry spices without burning them.

Same, I just turn a knob and it outputs the same BTUs every time - it isn't random.

>An induction stove can heat anything quickly, not just water. And importantly it can rapidly change temperature, unlike a resistance electric stove.

Again, I'm generally not too concerned about speed here. But yes, I'm very much concerned with changing temperatures quickly which involve not only the heat source but just as importantly, the cookware which leads me to....

> You can just use one of these:...The benefit of copper is supposed to be precision temperature control, but as you said, precise temperatures don't matter for day to day cooking.

Copper is a superior material because it changes temperature extremely quickly because it is such a great conductor - it's not about precision (except with candy making where induction could be great) rather than reactivity. When I turn the gas up the pan reacts to that change immediately and when I turn the gas down it reacts immediately to that. Unlike a material like cast iron which can store a lot of energy, it doesn't react to changes in input quickly so is not suitable for many things - you can't finesse a cast iron pan very easily. Seriously, get a nice gas range and a high end copper pan and cook with it - you'll be amazed. It's why so many chefs insist on the combination of gas and copper.

And no, I'm not buying one of those useless disks to make a copper pan work in induction. It kills the entire point of a copper pan and just gives you a cool, high-end look without the actual functionality. I'd feel like a complete fool because I would be.

I'm happy induction exists for people that want it or believe gas will harm them. But it's not for everyone and there's extremely good reasons many people want to cook over open flame. When I'm not using gas to cook you'll find me outside burning wood fires to cook with.

> Seriously, get a nice gas range and a high end copper pan and cook with it - you'll be amazed.

I cooked on gas for 25 years, including with all sorts of pots/pans. It was great and I preferred it greatly to resistance electric stoves. And then I switched to induction and couldn't be happier with both the cooking performance and the indoor air quality improvement. You (and many others) aren't concerned with or don't believe in the air quality problems of burning gas in a house. To each their own!

For my part, I tell everyone I know to maximize ventilation if they are cooking indoors with gas, and to try an induction stove to see if it works for them.

> When I'm not using gas to cook you'll find me outside burning wood fires to cook with.

That has nothing to do with the discussion about induction, but thanks for sharing, because I also love cooking over burning wood! We're more alike than you think!

> To each their own!

I think that’s the problem. There’s unelected officials suggesting they’re going to just ban them based on a biased (and very faulty - it isn’t quality science) study funded by activists groups. I’ve used induction and it’s ok but it doesn’t feel right to be, I can’t use materials I prefer, and I can’t do things like hold a pan a bit higher for a second, flambé, etc. I love induction for deep frying though. It’s much safer!

I have a 1300 cfm exhaust with a makeup air system so I’m not concerned.

Resistance does suck, but Halogen is pretty good IMHO.

> Of all the trades, electricity is the one that I know enough about to supervise somebody. (e.g. I am baffled by plumbing)

Curiously, we’re in opposite situations. I have a (very) basic understanding of electricity, just enough to change power outlets and the like. But in general I’m baffled by it because it’s a bunch of dangerous stuff I can’t see with values I don’t fully understand¹.

Plumbing, on the other hand, is water inside tubes controlled mechanically. Taking things apart reveals the simplicity of the system. After doing a fix I can feel confident in the safety and reliability of the work even before opening on the main valve again².

¹ If anyone has recommendations on a trustworthy course / YouTube playlist which teaches enough basics to understand electrical wiring in residential homes, I’m interested.

² I’m not doing super complex jobs, but in my own home it’s been years since I’ve needed to call a plumber.

I received a PhD in physics so I got a solid dose of electricity and electronics.

I did help teach an autotutorial class in physics for premeds which got me to do a little more with fluid mechanics than most people but the trouble I have with plumbing is finding documentation for the details.

For instance when it comes to sealing PVC pipes I have seen instructions that tell you to "refer to the documentation from the pipe manufacturer" which is not at all straightforward for pipes that have been there 20+ years.

Not a course, but this channel has a ton of interesting content on US residential wiring: https://www.youtube.com/c/technologyconnections

There are a lot of laws and regulations about electrical installations.

In many regions, doing it legally requires lots of courses and certificates. When you have invested all the time and money into getting said certificates, which is sometimes multiple years full time, you typically want to become a full time electrician to pay back the time+money investment.

That means that 'I just do electrics on the side' is becoming a thing of the past - at least in places with strict certification requirements.

Obviously in most parts of the world, there is no electrical police who will raid your home and look for evidence of wiring done without the correct certifications.

Therefore, lots of people DIY stuff illegally...

If you choose this route, understand that:

* The main cause of injury/death caused by electrics is fires. Fires are normally caused by improper fuses (a fuse/breaker should always be the lowest rating of any device/cable/connector downstream of it, unless that device has its own fuse), or badly made joints. Do joints properly with wago blocks or by tightening screw terminals very tight.

* The 'obvious' risk from electrics of electrocution is reduced to almost zero by installing a whole-house RCD/GFCI device. I wouldn't want to live in a house without one. And turn the power off before doing electrical work.

But not too tight, or the strands may break.

I have seen lots of near-fires/melted things from under-tightening, but I have never seen a single near-fire from overtightening. I suspect it's a myth - I don't think you could overtighten any connector sufficiently to make it be a fire risk without the screw shearing first.

I'd be interested to see tests demonstrating otherwise though.

Obviously if you are doing it to the standards, you crimp the wire first and use a torque screwdriver to tighten to the exact correct torque.

> I have seen lots of near-fires/melted things from under-tightening, but I have never seen a single near-fire from overtightening.

That depends what you see as near-fire ;) I recently helped out a friend whose lights had issues after she installed a more powerful fixture, turns out that the person installing it overtorqued the wire in the switch so much it nearly sheared off probably already during installation, and came completely apart when I took the switch out of the wall.

Better be safe than sorry and use Wago clips.

In most cases you use solid wire. In case you use stranded you should crimp the ends anyway, and crimping does exactly opposite, crushes wires so tightly they form practically solid metal.

Strands only break when wire moves and that would be the fault of bad stress relief, not "screwing it too hard"

And many places in the US allow homeowners to do work that nobody else can do without certification - sometimes even skipping the permitting.

It is still worthwhile to understand what you're doing, and how the breakers/GFCI/Arc fault will save your ass - and why they are NOT the same thing!

Wago blocks are wonderful, and I hope I'll never twist two wires together under a wire nut ever again.

Are you sure that's "illegal" or just "illegal to take money for it" ? Here (Poland) you can do it just fine on your own stuff as long as you don't pretend to be electrician and sell your service, with caveats (only touching anything after power company stuff IIRC)

In much of the US, you are allowed to do any work that you want to on your own property, though if a professional would be required to get permits and inspections to do the same work then you usually still have to get those permits/inspections.

There's a startup that is adding a battery to induction appliances, in part so that you can run off of a standard outlet: https://www.channingcopper.com

It's only in pre-orders, however. Edit: Looks like first round of pre-orders were limited to Bay Area and now there's a wait list for next round.

It's interesting that I've found the people who are comfortable with plumbing are very wary of electrical, and vice-versa.

Look for a "smart heat pump" water heater and you can probably get away without actually upgrading service unless you want to - 100 amp service can support a stove and water heater especially if the water heater is "smart" enough to not run when the stove is running.

You can also find a friendly electrician to "check off" on your wiring after you do most of the grunt work, this works well for areas that require permits even for homeowner-done work.

In Taiwan, electricians and plumbers are the same occupation.

When you're getting your certifications, you have to get both.

You can specialize in one, but you have to know plumbing and electrical work to pass.

I was thinking more on the DIY side; I'm entirely comfortable with electrical, but I worry I wouldn't "do" plumbing right (soldering copper, mainly; I have no issue with PEX); a friend of mine is the opposite.

Your comment implies that you could hook up a ordinary electric range but not an induction range.

I thought induction used slightly less energy. Or is it that it uses more energy for a shorter time so the net is less but the peak is higher?

I assume I could replace my electric stove with a stove with induction "burners".

I believe the answer is that induction is more efficient at getting heat into your food.

With electric, it heats up a coil that heats up your pan (and the air around it) that heats your food.

With induction, it skips the coil and simply heats the pan. The pans are specially designed to contain a heating coil in them which implicitly is closer to your food.

It also means the work surface tends to cool quickly (or never get hot in the first place), making it safer.

>The pans are specially designed to contain a heating coil in them which implicitly is closer to your food.

Just to note, you don’t need special pans to use an inductive stove. Any magnetic cookware will do, which includes cast iron and most stainless steel. As an intuitive rule of thumb, if a magnet will stick to the bottom, then it’s compatible.

The pan doesn't have a heating coil in it - it's just a solid slab of metal. However, that acts like a single turn of wire in a "coil" shorted out.

Induction compatible cookware doesn't have a heating coil. They just need ferrous metal in them. They can be clad in aluminum, with a ferrous core etc. A cast iron pan works fine, and most stainless steel cookware is fine. It's just the cheap teflon stuff that's out of luck.

> It's just the cheap teflon stuff that's out of luck.

And copper and aluminium. Some stoneware too as well as glass when needed.

Copper and aluminum can be used as a cladding around the ferrous metal core just fine. I guess you could do the same with some of the ceramics/stoneware as well.

It really isn't just fine. You lose the entire purpose of the pans and might as well be cooking on an electric stove at that point.

>The pans are specially designed to contain a heating coil in them which implicitly is closer to your food.

This is not correct. Any ferric-metal pan/pot will work. If a magnet can stick to your pot it will work.

I wonder did anyone did a comparision between ones sold as "induction" vs plain old steel pan.

Like, do the induction ones do something to make the heat distribution more equal compared to slab of steel ?

Induction ranges are more efficient, so to heat at the same rate as an ordinary electric range, use less energy. But many people want an induction range that is more powerful than a typical electric range.

Yeah an induction range most likely wouldn't require any more power than a resistive range. The only caveat to that is that higher end ranges might have higher power draws due to having more burners and such and induction ranges tend to be the higher end. That being said it looks like most ranges require a 40 amp circuit now, while code now requires wiring a new range outlet for 50 amps even if you put a 40 amp breaker on it.

As an aside, for those watching from home - you can put LARGER connections downstream of smaller ones (50 amp outlet on a 40 amp breaker) because the worst case is your breaker will flip.

You can put SMALLER outlets on a larger breaker (40 amp outlet on a 50 amp breaker) because the outlet is SUPPOSED to keep you from overloading it (and the outlet will actually be rated for more than the "plug size")

The DANGER you must avoid is having a 50 amp outlet on a 50 amp breaker but only having wiring between them that can support 40 amps - and the amount of amperage a wire can support DROPS over longer distances. So it's best to size everything correctly from the beginning.

Standard non-metallic 8 gauge wire is only allowed to handle 40 amps. If you want to put 50 amps to the outlet you need more expensive wire (most likely 6 gauge, but there are other forms of 8 gauge that are approved for 50 amps). Since most stoves only need 40 amps electricians will run non-metallic 8 gauge by default and put a 40 amp breaker on it - then since there isn't such a thing as a 40 amp outlet they have a 50 amp outlet on the other end.

Yeah the main relationship that matters is the breaker to wire.

There is a fun semi related thing. Can you put 15 amp outlets on a 20 amp circuit? The answer is yes you can, but only if there is at least two receptacles, and a standard duplex outlet counts at two receptacles.

Which is another reason you don't want to oversize a breaker; you can have ten, twenty two-receptacle outlets on a single circuit, and if lots of stuff was plugged in you could easily draw tens or hundreds of amps, which would melt normal Romex pretty quickly.

This is an exception to the electric code, not the rule.

Almost every outlet must be paired with the appropriate wire size and breaker. A 30A outlet must be backed with a 30A breaker (no exceptions!) and wire must be at least capable of carrying 30 amps. There's also restrictions on wire size based on the outlet/breaker, since certain breakers/outlets cannot handle certain wire sizes. For instance, NEMA 5-15 outlets generally can't support wire sizes above 12 gauge, so you're limited to 12 or 14 gauge only.

Electric water heaters don’t need to draw a ton of amps. 4500 Watt, 240V 50 gallon ones are common, which is under 20 amps. Induction stoves peak at twice that.

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