Submitted 9 months ago by FenrirIII@lemmy.world to technology@lemmy.world
https://www.youtube.com/watch?v=W96a8svXo14
It’s not fucking overkill. There’s no such thing.
I’m really disappointed with the video. That dude usually knows his shit, but he’s way off the mark here. It’s just plain wrong.
Getting a smaller charger might save a few hundred, but it will also increase your chances of burning the house down. Good fucking advise, huh.
Fuck that. You’ll always want to charge as fast as your main circuit breaker will allow.
Do you think a device with regulation circuits is more likely to be overloaded and start fires…?
My guess would be yes, somewhat, probably. but maybe not much. As he says in the last part of the video: If it gets hot, you have a problem.
Better ask an electrician.
The devices sold as “EV wall chargers” are not really chargers. They’re simple power suppliy units, whether or not it has bells and whistles to time the charging and what not.
The actual battery charger is in the car. It will attempt to suck as much energy from the PSU as it can and it will itself balance the load and all that. Having a separate unit also trying to regulate the load seems like something that will inevitably create more heat than necessary somewhere in that chain.
Generally speaking you do not need to protect the car from unstable supply. It will protect itself.
I will still recommend getting a proper “EV charger” to ensure that it can utilize all the phases unlike a regular garage plug. Also to ensure that it is properly grounded, which can be an issue for some cars.
At least here in Europe, where we have 3 phases. It’s much better to have all 3 phases wide open and let the car suck a little on each, instead of having it overloading a single phase through a granny plug.
I know the American 2 phase circuit is different, but I still believe it’s better not to put any more heat inducing obstructions in the chain.
How would it increase chances of burning the house down? Outlets are rated for a specific current draw and will have a matching breaker on the circuit, if your outlets are worn out or the breaker or wire is not matched correctly that’s not the fault of the charger.
I don’t disagree with this, but we have a detached garage and got quoted over $6k to retrench an upgraded line to it. I know he mentioned this condition in the video, but our driveway is so tight it would be an obstacle to put a charger just on the outside of the house.
In the meantime, we started using a regular outlet in the garage with the basic charger that came with our Ioniq and after 2 years have never needed anything more. Never even used a public charger.
My wife had to try charging on a 120V outlet last winter. The plug couldn’t even keep up with the battery heating requirements to actually start charging; the battery percentage was going DOWN while plugged in. It was -25°C outside though, so it’s a specific situation, but it’s actually why she had to try to charge; it’s a trip we can easily do without charging in the summer.
Car specific maybe? I was able to charge at -30
Maybe, I know Teslas are a bit power-hungry when parked.
We have a granny charger that came with one of our EVs that we use as a backup and with our caravan to charge on sites that allow it. As I am UK it tops out at 2.4kw (10A @ 240v) and its annoyingly slow even charging for more than 12 hours at a time.
Our main home charger is 7kw, and as we get cheap electric every night for 7p a KwH for 5 hours, we can charge about 40kwh in that time period. Means even our largest battery is fully charged in two nights from completely empty. If we tried that with the granny charger it would cost significantly more, as it would be up to 40p a KwH outside of the main hours and take 40 hours to charge the same amount.
Now if you doing only a few miles a day, less than 40 miles (4 miles per KwH, charge for the 5 cheap hours using the cars charging timer, charge 10 KwH), it might work out ok for you, but then charging every day cannot be good for the battery? I know it would get annoying quite quickly. It would also get pretty painful if you have more than one EV, we have three between us and the kids, so its not remotely practical.
Granny chargin’, not triple phasing like you should.
You almost had me charging? You never had me charging - you never had your car charging, it had tripped the socket
Pedantic but: 7kw isn’t three phase in the UK, just 30A. Three phase electric can give you up to 22kw in the UK for charging, obviously not every EV can charge that fast, most only go up to 11kw AC. I would kill for that extra charging speed but I can’t justify the extra cost and effort to get it fitted by the electric company
I watched the video and it seems to make good points, but no matter how many times I see something related to US power circuits it just feels so … antique? I have 3x25A fuses on the house and several 3x16A outlets around so getting 11kW out is just a matter of plugging in a socket.
Obviously it would be a good thing to have controls so that water heater, floor heating or sauna stove aren’t all on together but I think I’ve replaced a single 25A fuse over 10 years we’ve lived on this house and I’m pretty sure that was caused by a small(ish) surge on the grid and not our load.
What they do here for (a good amount of) home car chargers is read out the electricity meter using their serial port and dynamically adjust the charge current to never take more than those 3x25A.
Fuses sound antique compared to resettable circuit breakers. Though, if I remember correctly, your outlets have resettable breakers? Anyway, part of the wattage deficiency comes from the voltage being half of Europe’s. The wires are similarly sized so they hit about the same max amperage (largely 15a for most circuits, 20a frequently in kitchens/garages/exterior outlets, 100-250a main breaker for the house) but halving the voltage halves the wattage available
Though, if I remember correctly, your outlets have resettable breakers?
Here in Finland we don’t have breakers on outlets themselves, they’re all on electrical panel. But we have ‘automatic fuses’ which you can reset, they’re just referred as ‘fuse’ almost always. Also, as our house is older, the 25A main fuses are actual porcelain ones, but new ones obviously have those automated too. Similarily, nearly all of the fault current protectors are on electrical panel instead of individual outlets.
And in here nearly all fuses for lights, sockets and everything are either 10 or 16A with bigger main breakers, normally 3x25A for individual houses.
I’m not sure what you mean by this. Any modern US house would have a similar capability, it’s just older homes that would struggle since there would never be a need for such high power devices in a garage.
Most older garages would only need enough power to run a single lightbulb, if it was slightly newer, maybe a low power automatic garage door opener.
It’s the same in any country with buildings over 100 years old.
It’s the same in any country with buildings over 100 years old.
In here 100+ year old houses are pretty common but practically all of them still have at least somewhat up to date electrics with that 3-phase input. It’s been around for decades after all. My house is built originally 1928 and my mothers house is from 1909 and both of them have 3x25A main breakers with those 380V 16A CEE sockets around.
And as garages commonly double as a work space with 3-phase induction motors on the tools it’s still pretty common to have that 3x16A available as it’s not that much more expensive to pull 5x2.5mm² cable to the garage compared to 3x2.5mm² for single phase 16A outlet.
Yep – US also doesn’t generally do residential three-phase unlike many countries in the EU. A lot of garages around here have 3x16A 230V, not (only) due to the power requirements but because having three phases allows for simplest induction motors for things like blowers and circular saws. When you have three phases having a proper outlet in the garage starts making sense.
Around here (Finland more specifically) we have three-phase even in most apartments. My two bedroom apartment has a 3x25A main breaker, and two devices on 3x16A circuit’s – the sauna stove and oven+stovetop. Most single-family homes have 3x25A or 3x36A as well.
US households are missing out on a lot of things due to their split-phase system.
In recent test of a German suto club they found out that it‘s cheaper/ more effective to charger faster. You loose a lot of energy if you load slow over hours.
This energy is taken by the electricity of the car. So, while charging the car is on and takes some Watts/h. There are just a few brands that habe decoupled the charger circuit from the overall electric circuit of the car.
Can’t find the article now, but I think charging a PHEV through a standard power plug had about 20% energy lost. It was clearly visible that a charger is a good choice.
Yes, he responds to that in the video.
Watts/h
Just watts, watts is already Joules per second.
Did that account for battery lifetime, because if not, that could offset efficiency gains as fast charging degrades batteries.
I‘m not sure if fast charging degrades batteries. Just read somewhere an article stating that fast charging initially - first charge - boosts the overall capacity of the batterie due to chemical reactions that do not occur that long at anodes.
The issue with fast charging was the thermal management - it’s getting to hot. This is managed by good battery management and a different packaging of cells nowadays. I think fast charging isn’t an issue anymore. Can’t provide you a link or such, it’s what I gathered through serveral podcasts.
Any AC load you can throw at an EV is effectively “slow charging”. My car supports a maximum of 9.6kw from an AC charger, but up to 150kw from DC fast chargers. Even with the fast charging, its not like a phone, it has active thermal management which will cool the battery and slow down the charging if it gets too hot. phones don’t really have that and is mainly why they degrade faster if quick charged.
A small 30 amp level 2 charger can put another 10 miles of range in a 450 Wh/mi car in 40 minutes.
A 15 amp level 1 charger can put another 10 miles of range in a 450 Wh/mi car in 2.5 hours on paper, but practically it takes longer, over 3 hours if it downrates itself to 12 amps, and almost 5 hours if it chickens out to 8 amps.
Another 4.5 kWh of battery gets another 10 miles of range without charging.
Having a level 2 charger at home means any time you go home for just about any reason you can always take just about any trip again right away, without an expensive vehicle with an oversized battery.
You might not need 50 amps now. But that line is a 1 time cost and maybe you'll want to weld one day.
I agree with this youtube comment:
As an electrician (in Australia), I agree with your basic premise. However, if you are asking me to install an EV charger, unless you tell me “I want it to charge slowly with a limited current capacity”, I am going to assume it is to charge an EV under ALL situations - fast to slow, for whoever may drive one today or in the future, even with a potential new homeowner. We generally do our work with the priority order (1) safety - nobody gets an electric shock and nothing catches fire; (2) avoidance of nuisance i.e. the thing you just installed doesn’t work and keeps tripping the breaker 😑 (3) avoiding needing replacement electrical work for at least 25 - 50 years
Also I live in a townhouse with no garage. Our charger is between the neighborhood sidewalk and our parking spaces, so I’d prefer keeping it unplugged as often as possible to minimize any issues with foot traffic (neighbors, delivery people, garbage pickup, etc). I’ve seen other people literally run an extension cable over the sidewalk to do an L1 charge for their EV and that’s just asking for trouble.
He did say that it’s different if you don’t own your own garage or live in a townhouse
Personally, I’m on an electricity plan that gives me free usage at midday when solar is flooding the grid, so it’s useful for me to be able to charge as fast as possible in that window.
Faster charging is useful for more than just finishing before your next drive.
Yeah I don’t need to refill my battery in 2 hours, but it’s nice to be able to meaningfully top off between errands to make the most of a small PHEV battery.
I think “might be overkill” would be a better title and position than “usually overkill.”
There is absolutely a subset of EV drivers that could get by with a level 1 charger (ignoring time of day rates), but most people would fall behind anytime they drive further than the average number of miles. Sure, taking 10 hours to recharge your Chevy Bolt overnight when you’ve driven 40 miles is doable; 64 hours when you’ve returned home from a longer trip isn’t.
I own a PHEV, and installing a level 2 charge has been one of the best quality of life and financial changes.
I think “might be overkill” would be a better title and position than “usually overkill.”
It factually is not.
most people would fall behind anytime they drive further than the average number of miles.
Assume you drive it all the way to empty, then park it and plug it back in at 7PM. Leave it for 12 hours until you leave again in the morning. A typical small EV will charge at ~5MPH on a 110V, 1.2kW connection (faster on a 20A circuit). So 5MPH x 12 hours means you already have 60 miles of range again for the next day. And I would say that’s a pretty extreme scenario.
I use L1 almost exclusively, BTW.
Congrats on finding a solution that works for you. I have a short commute (16 miles round trip) and was OK to use L1 charging on a “usually” basis. However, I do more things in my life than just going to work and back. After work I might drive another 90 miles round trip to meet some friends at a brewery. Or I might drive only a couple miles to a buddy’s house and not get home until 11pm, so I now only have 7 hours to charge at L1 instead of 12 hours. And on weekends when I’m maybe driving a couple hours to hike in the desert and come back, I now have 16 hours to charge for work on Monday after driving 210 miles round trip.
Switching from L1 to L2 charging at home made driving an EV go from a daily chore to something I almost never thought about.
What electric vehicle gets 5 miles/1.2kWh? That’s only 240 Wh/mi.
It factually is not.
Factually, it’s not either. Both are statements of opinion, although I’d say saying the word “usually” should have some degree of proof behind it.
My statement of “might be” recognizes that there are many instances that L1 makes sense, and I agree with the video that for those for whom it does shouldn’t needlessly install a 240v outlet. Sounds like you’re among those.
I’d say that, sadly, most EV drivers drive more than 40 miles per day on average, and that the moment you drive more than 60 miles per day you’ll have difficulty recharging to full. Most days, you’ll have no trouble recharging overnight. But if you’re like me, you might take a day trip over 100 miles away a handful of times per year. When that happens, I’d arrive home with very little battery left; am I supposed to have the ability to charge for 50 hours?
Agreed, and that headline is needlessly inflammatory . Looking at my mileage , I could almost certainly get away with just plugging into a standard outlet. However the level 2 charger means that even if I screw it up, I can be mostly charged in a couple of hours. It’s been really effective at helping me get over what range anxiety I had. It’s really helped keep car usage as a somewhat impulse thing, rather than a process: I’m ready to go anywhere anytime
If you screw up, you can usually get to a charger a few blocks away and snag 50% of your battery in 20 minutes.
I charge entirely off of a standard 120 outlet, and it easily handles my daily and weekly travel needs, along with my partner’s numerous errands and extra trips throughout the week.
Yep the difference for our setup was going from 12-18 hour full charge times (Level 1) to about 6 hours on Level 2. L1 charger could only put out 12 amps at 120v, and while the L2 charger can do up to 50A of 240v power, our vehicle can only use about a third of that capacity at max draw.
So as the video’s topic covers, we didn’t need a 50A circuit for Level 2 charging on our limited vehicle. But I put in a full 50A circuit anyway so now I can eventually upgrade our other car to electric or PHEV and be ready for whatever those need.
What kind of range do you have on that? I’ve been debating installing a l2 charger because overnight charging is usually good enough. I tend to get about 15-20 miles range tops on pure electric.
The way I explained it to my brother:
30-35 miles, depending on the season.
Good video. Accurate information.
Two notes:
For North American homes: I agree with the overlooked value of a downrated circuit for EV charging, but I don’t think he talked about a possibly better option for downrating: Using an existing 120v circuit (at whatever current rating) already wired in the garage . Remove the outlet, install EVSE (charger), and swap the breaker for a 240v one (at a current rating matching the original. So if you have a 120v 15A circuit (white romex) you can use the exact same wire for a 240v at 15A. If you have a 20A (yellow romex) you would end up with a 240v 20A. You get more than double the speed of charging with zero new wires added, only changing the breaker and removing the old outlets. Note: If you have multiple outlets in your garage all fed from this same circuit, this would mean all of your outlets in the garage are now 240v and not usable for regular 120v items.
He didn’t like Smart chargers. Thats a valid opinion, but smart chargers can do some nice things that I like. Some will also talk to each other if you have two chargers, such as if you have two EVs. They can be configured to share the same wire to the breaker box, so you can plug both cars in at night, one car will charge, then when that is complete, the other will charge automatically without having to unplug one car and then plug in the other. It will charge the least charged car first ensuring the best balance of charge to both cars assuming both cars can’t be charged to full in one night. If you have solar panels, some smart chargers can talk to the solar system and be instructed to only charge when there is excess power that would otherwise go to waste. It can do this automatically so if clouds go overhead and not enough juice is available from the sun, the charging stops. As soon as the clouds clear and there is an excess again, charging resumes automatically. For outdoor charging, you can also configure most Smart chargers to only charge you authorized cars. So you don’t need to worry about someone rolling into your driveway when you’re not home (or a bad neighbor) and running up your electricity bill.
For me the smart charger was a key feature, and I never understood why that is never talked about. I have 200a service which was plenty for one fully powered charging service, but with the likelihood of electrification in upcoming years I was hesitant to have two. It was pretty clear I needed to prioritize smart charging so I’d have that possibility.
So far my family only has the one EV, so we only need the one charger. But I like that if we needed a second charger it could be on the same circuit and they could dynamically share the power to maximize charging
#1 is a terrible idea if you ever need to hire an electrician in the future, plan on selling your house, etc. The National Electric Code prohibits using white, green, or grey wire for a hot/load connection. The 120V cable will contain a black wire for the hot connection, white for neutral, and green for ground. To properly convert it to 240V you would need a cable that consists of black & red wires for the two 120V legs.
If your home ever suffered an electrical fire then this sort of jury rigging is precisely the sort of thing any competent insurance inspector would spot, and insurance carriers would deny coverage for since it clearly isn’t code compliant, which means a licensed electrician didn’t install it and it wasn’t properly inspected.
The “120 volt cable”, assuming you mean NM-B aka Romex, is rated for up to 600 volts if you look at it closely. It is absolutely acceptable to use that wiring for a 240V circuit, as long as you wrap colored (not green) electrical tape around the white neutral wire to indicate it’s another hot.
Yes, there are 3-conductor (plus ground) wires one can also use for switches and 240V circuits with neutral. That neutral can be used to have 120V and 240V together (your oven may use 240V coils, but the light bulb probably runs on 120). Doesn’t mean you need to have it, if your 240V circuit doesn’t need a neutral. My air compressor is just a motor that can run at 240, no neutral needed, and its outlet is wired up with the same kind of Romex used for a 120 right next to it (with black tape to indicate a second hot)
#1 is a terrible idea if you ever need to hire an electrician in the future, plan on selling your house, etc. The National Electric Code prohibits using white, green, or grey wire for a hot/load connection. The 120V cable will contain a black wire for the hot connection, white for neutral, and green for ground. To properly convert it to 240V you would need a cable that consists of black & red wires for the two 120V legs.
I’ll be the first to admit I’m no certified Sparky, but wire relabeling is used in a number of situations fully in accordance with NEC. My understanding is that some of this is in NEC 200.7. It requires relabeling both ends, but I don’t think there’s any code violation with it. If what you’re saying was true, wouldn’t that mean any -2 NM (Romex) would be code incompatible with 240v loads? I don’t think that’s true.
A 240V 20amp circuit I think would meet the needs of 99% of commuters in the US. If your average miles/kWh is around 3.3 and you’re charging at 80% of the 20amp breaker limit (as you should be), even factoring in 10% losses in power transmission, you’re still charging somewhere around 11 miles per hour. Easy 100+ miles overnight with zero infrastructure change outside of a couple wire nuts and a cheap charger. Hell, depending on local codes, you might get away with slapping in a nema 6-20 receptacle to make it even easier…
Hell, depending on local codes, you might get away with slapping in a nema 6-20 receptacle to make it even easier…
If you do a receptacle, you’ve got to then do a GFCI. Check out the price difference between a GFCI breaker and one that isn’t. If you hardware the EVSE, you don’t need GFCI because GFCI is built into nearly all EVSE. If we’re doing this exercise to keep low costs, adding GFCI outside of the EVSE jacks up the price.
could this be an article instead of a video? I’m not spending 32 minutes watching this, tbh
Yes. In a nutshell it’s “if you don’t know about electric cars, here’s some information you probably don’t know as well”
You should give it a shot. The dudes videos are super captivating.
For me, they’re captivating for about 5 minutes. Then the dry humor and constant cries of outrage become irritating. He could probably make 15-20 minute, info-dense videos without all the extra “personality”.
This has to be my favorite thing about Jeff Geerling vs other YouTube channels, he’ll make an accompanying blog post to go with each of his main channel videos that is effectively an annotated text version of the video with appropriately embedded images and links.
Lots of them do that if you look.
Highly recommend Technology Connections for anyone interested in easy to understand, relatable breakdown videos of technology.
antimidas@sopuli.xyz 9 months ago
One thing I really don’t get in the discussion around EVs and charging is, why are people so afraid of tripping the main breaker? If you have a total of e.g. 17 kW available and happen to go over, just reset the main breaker (or replace it in case it’s still a traditional one). It’s there precisely so that you wouldn’t need to care about overloading the connection.
In my experience people get by with a 3x25A (17 kW available, matches approximately a 70A service in the US) while using the available power to
While it’s true you can trip the main breaker if you have everything on at the same time, typically it never happens even if there are no lockouts in place preventing overuse. And it’s not like tripping it causes any permanent harm.
Why is an electrical service upgrade constantly brought up as a solution when any home with >15 kW of available power won’t need it? Is it against code to purposefully overcommit your mains in the US or something?
Ibuthyr@lemmy.wtf 9 months ago
I’m not afraid of that at all. But if you draw shit tons of power from a crappy socket, things start to heat up real quick. Like getting really fucking hot, as in burn your house down hot.
Ilovethebomb@sh.itjust.works 9 months ago
Where I live, there is a pole fuse, which is, as the name implies, on the pole, and only a linesman can change it.
Massive pain in the ass if
Nexz@feddit.nl 9 months ago
Yes… I have experience here. I’m using dynamic energy tariffs so during real sunny weekends the price can be negative - I get paid to consume power. As you’d might imagine, I charged the EV, disconnected my solar panels, turned on all HVAC to max cooling and set both my ovens to clean-mode……… Put some clothes in the dryer, tripped my fuse and cost me €140,- to replace it. Also, power for that phase went out which contained one of the ovens, which was midcycle. Couldn’t cool itself down, melted the plastics 😬. But at least I gained €4 during the timeframe it worked.
driving_crooner@lemmy.eco.br 9 months ago
Not everyone know as much as electricity as you, I think is natural to be afraid of something you not know so much and that potentially can burn your house.
AA5B@lemmy.world 9 months ago
Wow, how do you do that?
Of course over-provisioning is a thing but that’s crazy. Maybe you have much smaller appliances or assume much lower usage, but 70a basically assumes 2 major appliances at a time, using close to max load, and with nothing else turned on.
Typical 240v major appliances
Of course you won’t use them all at once and they won’t usually be drawing their full rated load but I would not want to deal with being limited to one at a time so I can also turn on the lights or use the microwave
antimidas@sopuli.xyz 9 months ago
Let’s go for a standard single family home example. Level 2 charger is either 8 A (5.5 kW) or 16 A (11 kW) three phase. On top of that, typical sauna is 6-7.5 kW, 1-2 heat pumps (approx. 1.5 kW a piece), stove (8.5 kW max), water heater (2-3 kW), + other appliances like dishwasher, washing machine etc.
It would seem like that easily trips the breaker, but you won’t be charging the car and warming up the sauna at the same time, unless opting to 5.5 kW charging. However, you typically charge the car at night, when the other things running are the heat pumps and the water heater – this will end up drawing around 16 kW total (in the worst case scenario) which fits in the limit. When you don’t count the car into the mix, there’s plenty of power to go around.
There are multiple reasons behind this. One is our homes are relatively well insulated, which means that we can get by with a lot less AC and heating. Appliances in the EU are also generally more efficient – as an example, our dryers are typically based on heat pumps and pull a lot less amperage for the same performance. Lot of homes also don’t have a dryer. Stoves have generally lower power requirements as well, and practically never draw peak power. Here’s an example washer+dryer combo where the suggested fuse for the whole thing is 10 A (meaning 2.3 kW available for the combo).
So listing the same appliances you have (at 230 V single phase equivalent for simplicity, i.e. 75 A available (3 * 25))
Which will result in 79 A total worst case or 103 A depending on the car charger spec. A bit over the 75 A available, and not calculating additional smaller loads like the microwave, kettle, TV, lighting etc. That worst case will in practice never be reached, though, and even the main breaker typically has some tolerance before it trips (usually main breaker is using a slow-blow fuse equivalent profile, which doesn’t immediately trip with a minor overload or a short spike). Our code mandates enough tolerance in wiring gauges that this doesn’t pose any risk.
Why don’t we want the added headroom then? Upgrading the service from 3x25A to 3x35A isn’t really that expensive in urban areas, and can be done relatively simply? Well – Finns are stingy and depending on who happens to own your local distribution grid you can get heavily penalized monetarily in the long term, when upgrading the service to a higher tier. Caruna owns a lot of the Finnish distribution grid nowadays, and as an example from their pricing chart going from 3x25A to 3x35A raises your monthly base rate from 29.71 € to 51.68 €. That’s 240 € extra per year, which is a pretty high cost for a just in case that’s easily avoided. In cities that still have municipally owned distribution (Lahti, Turku, Helsinki as an example) the costs are typically much lower, both for upgrading the service and monthly costs, compared to the privately owned grids.
Zenith@lemm.ee 9 months ago
Aside from the heat pump we have all of these things and they’re often running all at once. Never had an outside
mholiv@lemmy.world 9 months ago
The way that it works in most countries is that the breakers are per circuit in your wall. The breakers trip in order to prevent that single circuit from overheating and starting a fire in your walls.
Let’s say you have a wire that’s rated for 16amps. More than that and it becomes a fire risk just threw overheating. @230v that gives you 3680w per circuit.
If you have your industrial microwave, water heater, and car charger all going at the same time on that same circuit that will draw way more than 3680w and thus would go over that 16a limit.
The breakers trips once you go over that 16a limit for safety. It’s a good thing. This all being said no sane electrician would put those three things on the same circuit. lol.
I know it works this way in the U.S. and Germany at least.
mic_check_one_two@lemmy.dbzer0.com 9 months ago
Also worth noting that breaker ratings are for instantaneous usage. A 15A 120v breaker can only actually support 12A of continuous usage. But it says 15, because most things use a little extra power when they first turn on. AC system spinning up the fans and compressor, for instance. If you put a 15A device on a 15A breaker, it would likely trip as soon as that device turned on. In that instance, you’d likely use a 20A breaker to support the 15A device instead. But that 20A breaker would also call for upgraded wiring and outlets which could support 20A.
antimidas@sopuli.xyz 9 months ago
Not talking about the circuits, but the main electrical connection to the grid. To me it often seems like there’s reluctance in overcommitting that capacity: as an example, four 16A circuits on a 25A main breaker. Here that’s quite common, but even in Tech connections videos I’ve seen him bring up smart electric cabinets or automatic load monitoring when putting enough capacity on the mains to possibly go over.
What I’m asking is, why bother? If you trip the mains by having too much load, just reset the breaker and be done with it. No need to automate things to not run into that situation, one will learn to not have the oven on while charging the car full blast. No need to gimp with the charger amperage since you’re running a new circuit anyway.