WEBVTT Kind: captions Language: en-US 00:00:00.110 --> 00:00:04.180 This video has had something like seventeen false starts. 00:00:04.180 --> 00:00:08.060 I’ve gone down a number of rabbit holes trying to understand a bunch of things, 00:00:08.060 --> 00:00:12.500 and I had at one point committed to making an entirely different video because of that! 00:00:12.500 --> 00:00:15.269 But then I ran into a number of conceptual hurdles 00:00:15.269 --> 00:00:17.120 that I don’t have the energy to address right now 00:00:17.120 --> 00:00:20.700 so we’re back to the simple scope of that first one. 00:00:20.700 --> 00:00:24.970 Now, I’m gonna be honest here, my main point with this video is to address a grievance 00:00:24.970 --> 00:00:28.560 I have with how the rest of the world seems to understand the United States 00:00:28.560 --> 00:00:31.380 (and more broadly North American) electrical system. 00:00:31.380 --> 00:00:36.280 While it’s true that we have terrible, barely adequate receptacle designs 00:00:36.280 --> 00:00:38.500 and our kettles are slower than yours, 00:00:38.500 --> 00:00:42.380 here’s a fact about us that I think will blow a few fuses out there; 00:00:42.380 --> 00:00:45.930 The US is a 240 volt country. 00:00:45.930 --> 00:00:47.220 I can hear a lot of you going 00:00:47.220 --> 00:00:48.140 whaaaa???? [with obnoxious buzzing and other sound effects added] 00:00:48.140 --> 00:00:49.360 But it’s true! 00:00:49.360 --> 00:00:53.820 We have 240V in our electrical panels and at our disposal. 00:00:53.820 --> 00:00:56.720 You’ve heard about our obsession with air conditioning, right? 00:00:56.720 --> 00:01:00.710 Did you really think we’re cooling our gaudy McMansions with a machine we just 00:01:00.710 --> 00:01:02.740 plug into a regular outlet? 00:01:02.740 --> 00:01:03.600 No. 00:01:03.600 --> 00:01:05.280 And some of us have electric stoves, 00:01:05.280 --> 00:01:06.340 electric water heaters, 00:01:06.340 --> 00:01:07.240 clothes dryers, 00:01:07.240 --> 00:01:09.880 and even electric vehicle charging now! 00:01:09.880 --> 00:01:15.520 We’re not doing all of those things with a measly 15 amps at 120 volts (Or 1800 watts). 00:01:15.520 --> 00:01:17.020 How are we doing it, then? 00:01:17.020 --> 00:01:21.260 Let’s take a trip to the other room where I have a standard US service panel we can look at. 00:01:21.260 --> 00:01:24.240 [electrical humming] Here’s a standard US service panel we can look at! 00:01:24.240 --> 00:01:25.760 It might be a little hard to hear -- 00:01:25.760 --> 00:01:27.260 [humming abruptly stops] I'm just kidding. 00:01:27.260 --> 00:01:29.640 I added that 60 Hz hum in post. 00:01:29.640 --> 00:01:33.880 Did you seriously think our service panels are some sort of disastrously loud thing? 00:01:33.880 --> 00:01:35.240 I bet some of you did. 00:01:35.660 --> 00:01:38.340 Anyway, this building is a single family home. 00:01:38.340 --> 00:01:41.580 That’s important because of a little thing I’ll be bringing up later. 00:01:41.580 --> 00:01:46.680 Now, this little wart thing on the side is a doorbell transformer - pay no attention to that 00:01:46.680 --> 00:01:52.180 and, uh, also, um any of the wires that might seem a little less, uh, tidy than others 00:01:52.180 --> 00:01:54.980 are the work of yours truly but, again - not important! 00:01:54.980 --> 00:02:01.020 Now inside we’ll find a main breaker at the top and a bunch of, in fact to many people 00:02:01.020 --> 00:02:04.880 an absurd number of circuit breakers feeding individual circuits. 00:02:04.880 --> 00:02:07.740 But there’s still room for two more! 00:02:07.740 --> 00:02:10.700 The main breaker is a 200 amp breaker. 00:02:10.700 --> 00:02:16.600 This home, like many and pretty much all homes built within the last few decades, has 200A service. 00:02:16.600 --> 00:02:22.560 Now, you might be thinking that’s 200A at 120V so we have 24 kilowatts at our disposal here. 00:02:22.560 --> 00:02:27.100 But no, that’s 200 amps at 240 volts, so in fact 00:02:27.100 --> 00:02:30.100 many homes have 48 kW to go around. 00:02:30.100 --> 00:02:34.100 100A service is still fairly common but that’s still 24 kW. 00:02:34.100 --> 00:02:38.960 Plenty for smaller homes, especially since natural gas or other types of fuel combustion 00:02:38.960 --> 00:02:42.520 for space heating is still quite common ‘round these parts. 00:02:42.520 --> 00:02:47.000 Now, take a look at these breakers and you’ll find that they have their capacity printed on their toggles 00:02:47.000 --> 00:02:50.560 and you’ll also see that a few of them are… weird. 00:02:51.160 --> 00:02:53.400 They take up two spaces for some reason. 00:02:53.940 --> 00:02:54.840 Huh. 00:02:55.120 --> 00:02:57.740 Well, those are 240V circuits. 00:02:57.740 --> 00:03:02.020 This one’s going to a clothes dryer, this one to an air conditioner, etc. 00:03:02.020 --> 00:03:04.080 But… why two spaces? 00:03:04.080 --> 00:03:06.240 That seems a little weird, doesn’t it? 00:03:06.240 --> 00:03:11.640 Well, the reason it takes up two spaces has to do with the weird way we get 240V. 00:03:11.640 --> 00:03:16.120 You see our power transformers that feed our homes do produce 120V. 00:03:16.440 --> 00:03:17.720 But twice! 00:03:18.060 --> 00:03:22.460 Yeah! It’s weird! But first, a quick reminder of what transformers do; 00:03:22.460 --> 00:03:24.160 They’re more than meets the eye. 00:03:24.160 --> 00:03:28.349 Pretty much THE reason we use AC power all over the place is that we can 00:03:28.349 --> 00:03:31.840 use transformers to step the voltage up and down all will nilly. 00:03:31.840 --> 00:03:36.730 All you gotta do is wrap a bunch of wires around an iron core, and they’ll induce an electromagnetic field 00:03:36.730 --> 00:03:40.630 which propogates through it! Then, wrap some more wires around the core on the other side 00:03:40.630 --> 00:03:45.080 and that field will induce a current in those wires! Simply vary the number of turns of 00:03:45.080 --> 00:03:49.580 wire around the core on each side and you can change the voltage according to that ratio! 00:03:49.960 --> 00:03:50.920 It’s pretty neat! 00:03:50.920 --> 00:03:56.400 It allows us to transmit power through overhead or buried electrical lines running at thousands of volts. 00:03:56.400 --> 00:03:59.720 That lets those wires carry a ton of power for their size, 00:03:59.720 --> 00:04:03.230 because while the cross-sectional area of any given conductor affects how much 00:04:03.230 --> 00:04:08.909 current it can safely carry, when you bump the voltage way up you can carry more power 00:04:08.909 --> 00:04:13.880 (that’s watts) with the same amount of current and thus a relatively small cable. 00:04:13.880 --> 00:04:19.160 This allows us to transmit power over long distances economically in the near megavolt range. 00:04:19.160 --> 00:04:24.540 Substations will step that down to a more reasonable 11 or maybe 32 *thousand* volts 00:04:24.540 --> 00:04:26.050 for neighborhood distribution, 00:04:26.050 --> 00:04:30.669 and right before it enters your home it is stepped down by a final transformer which 00:04:30.669 --> 00:04:34.420 delivers the final, relatively low voltage to your home. 00:04:34.920 --> 00:04:39.100 Now, normally, you just hook a couple of wires up to the ends of the secondary winding of 00:04:39.110 --> 00:04:41.260 the transformer and call it a day. 00:04:41.260 --> 00:04:43.600 That’s what you’ll find in most countries around the world 00:04:43.600 --> 00:04:46.420 when dealing with standard single-phase electric service. 00:04:46.420 --> 00:04:48.720 [whispers] We’re just gonna ignore three-phase for right now. 00:04:48.720 --> 00:04:52.599 The secondary winding produces a 240V potential and thus 00:04:52.599 --> 00:04:55.480 you get 240V out of that transformer. 00:04:55.480 --> 00:05:00.720 And believe it or not, that’s exactly what our transformers do! 00:05:00.720 --> 00:05:05.860 They produce 240V on the secondary winding, just like yours. 00:05:05.860 --> 00:05:07.740 But the weird bit is that 00:05:07.740 --> 00:05:09.600 This is America. 00:05:09.600 --> 00:05:13.520 We’re not gonna settle for hooking up a measly two wires to our transformers. 00:05:13.520 --> 00:05:15.560 That is simply unamerican. 00:05:15.560 --> 00:05:18.060 No, we must have three. 00:05:18.060 --> 00:05:20.560 That’s one more and thus better. 00:05:20.560 --> 00:05:21.860 Obviously. 00:05:22.349 --> 00:05:24.440 This is where the weirdness happens! 00:05:24.440 --> 00:05:28.680 Our transformers don’t just have taps on the ends of the secondary winding. 00:05:28.680 --> 00:05:32.440 We put a third, central tap right smack dab in the middle, 00:05:32.440 --> 00:05:35.088 or center, of that winding in its middle. 00:05:35.088 --> 00:05:38.180 And that center tap becomes referenced to Earth, 00:05:38.180 --> 00:05:40.560 and that is what defines our neutral. 00:05:40.560 --> 00:05:43.860 Doing this creates what is called split-phase power. 00:05:43.860 --> 00:05:48.280 We end up with what behaves as though there are two 120V potentials 00:05:48.280 --> 00:05:51.500 180 degrees out of phase from one another. 00:05:51.500 --> 00:05:55.540 Across either of those and neutral you get 120V, 00:05:55.540 --> 00:06:01.980 but when you go across the two phases you end up with the full 240V the transformer is producing. 00:06:01.980 --> 00:06:04.267 So now let’s go back to the electrical panel. 00:06:04.267 --> 00:06:08.420 I’m going to take the cover off of it so you can see what’s going on inside. 00:06:08.420 --> 00:06:09.920 This is the part where I say 00:06:09.920 --> 00:06:11.960 Don't Try This At Home! 00:06:11.960 --> 00:06:16.560 There are many things inside this box that can kill you if you touch them. 00:06:16.560 --> 00:06:20.040 I have a fairly good understanding of what those dangers are in here; 00:06:20.040 --> 00:06:23.800 good enough to run a few new circuits without injuring myself or burning the house down 00:06:23.800 --> 00:06:26.300 with, so far, a 100% success rate. 00:06:26.300 --> 00:06:29.220 But this is not something to play around with. 00:06:29.220 --> 00:06:32.140 I’m showing you mine so you don’t need to see yours. 00:06:32.140 --> 00:06:32.930 Kay? 00:06:32.930 --> 00:06:35.800 Alright. Here’s where the magic happens. 00:06:35.800 --> 00:06:39.860 I know, to those of you in Europe this looks horribly gross and terribly unsafe but 00:06:39.860 --> 00:06:42.160 that’s OK. We're coping. 00:06:42.160 --> 00:06:46.480 Up at the top there are three beefy cables coming in. 00:06:46.480 --> 00:06:50.660 Those come from the meter box outside but ultimately from the transformer. 00:06:50.660 --> 00:06:55.520 The two outer cables are both live at 120V potential to ground. 00:06:55.520 --> 00:06:58.260 The middle cable is, conveniently, 00:06:58.260 --> 00:07:01.000 ground. And also neutral! 00:07:01.000 --> 00:07:04.699 Yes. That middle cable is connected to a ground rod outside 00:07:04.699 --> 00:07:09.200 by the meter box, in addition to being connected to the center tap of the transformer. 00:07:09.200 --> 00:07:13.220 For those that didn’t know this already, the ground plug and the neutral plug 00:07:13.220 --> 00:07:18.340 of your electrical outlets usually end up in the same exact place eventually. 00:07:18.340 --> 00:07:19.400 Right here! 00:07:19.400 --> 00:07:20.700 (and on the other side) 00:07:21.920 --> 00:07:24.780 It’s weird and I don’t wanna get into it right now because it hurts my brain 00:07:24.780 --> 00:07:26.389 and there are particular exceptions 00:07:26.389 --> 00:07:29.080 so we’re just avoiding that whole can of worms. 00:07:29.080 --> 00:07:32.000 If I take a voltage measurement between this cable and the neutral, 00:07:32.000 --> 00:07:34.820 you’ll see that it’s 120 volts (or thereabouts). 00:07:34.820 --> 00:07:39.580 If I measure from the other cable to neutral it is also 120 something volts. 00:07:39.580 --> 00:07:44.680 Remember those two pairs of cables are across only half of the transformer. 00:07:44.680 --> 00:07:48.100 Conveniently they end up in the panel in that same orientation. 00:07:48.100 --> 00:07:50.360 This is the left side of the secondary winding. 00:07:50.360 --> 00:07:51.760 The right side of the secondary. 00:07:51.760 --> 00:07:53.980 And the center tap of the secondary. 00:07:53.980 --> 00:08:00.440 You will only get half the voltage of the secondary if you’re across only half of its length. 00:08:00.440 --> 00:08:06.960 But across those two outer cables you do in fact get 240V. Or close, anyway. 00:08:06.960 --> 00:08:13.040 Those two cables are at the ends of the transformer’s secondary so the entire potential is there. 00:08:13.040 --> 00:08:17.300 But you have to be across those two cables, not just across one of them and neutral, 00:08:17.300 --> 00:08:19.040 to get the full potential. 00:08:19.040 --> 00:08:24.380 And that’s why our 240V circuits are on these weird double breakers. 00:08:24.380 --> 00:08:30.159 The lugs up here feed a pair of bus bars going all the way down through the center of the panel. 00:08:30.159 --> 00:08:34.399 A circuit breaker makes contact with that bus bar and provides an internal link to an 00:08:34.399 --> 00:08:36.740 output on a screw terminal. 00:08:36.740 --> 00:08:39.120 The breaker can interrupt the current path from the bus bar 00:08:39.120 --> 00:08:42.340 to the terminal either manually with the toggle 00:08:42.340 --> 00:08:44.540 [two clicks as it is actuated) 00:08:44.540 --> 00:08:47.800 or automatically in the case of an overcurrent event. 00:08:47.800 --> 00:08:51.040 This here is all a typical US circuit breaker is. 00:08:51.040 --> 00:08:51.580 [click] 00:08:51.580 --> 00:08:52.440 [clack] 00:08:52.440 --> 00:08:55.940 It’s attached only to the live or hot side of the circuit. 00:08:55.940 --> 00:08:59.400 The neutral side of any circuit goes directly back to the panel. 00:08:59.400 --> 00:09:04.330 If you look in the two spaces where there aren’t a breaker installed you can see the contacts from the 00:09:04.330 --> 00:09:06.840 bus bars that the breaker will attach to. 00:09:06.840 --> 00:09:09.279 On the bottom of the breaker, this contact 00:09:09.280 --> 00:09:14.240 will clamp onto the bus bar, which through the switch contacts inside the breaker eventually 00:09:14.240 --> 00:09:16.680 make it to the output terminal here. 00:09:16.680 --> 00:09:19.480 The other bit is just to physically attach the breaker 00:09:19.480 --> 00:09:23.500 to the panel more sturdily via this plastic peg thing. 00:09:23.500 --> 00:09:26.700 The bus bars, though, aren’t just going straight down the panel. 00:09:26.700 --> 00:09:29.580 They’re a sort of interlocking comb shape. 00:09:29.580 --> 00:09:33.250 What this does is make it so that every alternate position 00:09:33.250 --> 00:09:37.520 down the panel is being fed by the opposite lug up there. 00:09:37.520 --> 00:09:42.060 In fact, you can see that one of the spots on the bus bar is connected to the right, 00:09:42.060 --> 00:09:44.040 and the other is connected to the left. 00:09:44.040 --> 00:09:47.680 Now, if you take a look at these two circuit breakers, they’re both feeding 00:09:47.680 --> 00:09:50.180 their own 120V circuits. 00:09:50.180 --> 00:09:54.649 But they aren’t themselves fed by the same cable up top. 00:09:54.649 --> 00:09:58.840 Take a look - across these two breakers there’s actually 240V. 00:09:58.840 --> 00:10:02.880 That’s because one breaker is attached to this cable through the bus bar. 00:10:02.880 --> 00:10:04.220 (I'm pointing to the left one) 00:10:04.220 --> 00:10:07.320 And the other one is attached to the other. (that's the right one) 00:10:07.320 --> 00:10:11.460 Again, each one of these breakers is feeding a different circuit. 00:10:11.460 --> 00:10:14.520 If you follow the wire coming out from the breaker, 00:10:14.520 --> 00:10:20.280 you’ll see that it joins up with a white neutral and a ground wire in one of these various cables. 00:10:20.280 --> 00:10:23.960 Those cables; they go to the various circuits in the building 00:10:23.960 --> 00:10:26.540 (or rather they are the various circuits of the building) 00:10:26.540 --> 00:10:29.819 and in the 120V circuits across the black hot wire 00:10:29.819 --> 00:10:32.960 and the white neutral wire you have 120V. 00:10:32.960 --> 00:10:36.160 The circuit breaker is there mostly to protect the circuit from 00:10:36.160 --> 00:10:41.259 being overloaded and damaging the conductors, or worse, starting a fire. But in conjunction 00:10:41.259 --> 00:10:46.420 with a grounded appliance it will also remove voltage should the 120V potential come in 00:10:46.420 --> 00:10:50.990 contact with the grounded casing because that effectively becomes a dead short which will 00:10:50.990 --> 00:10:53.500 trip the breaker more or less instantly. 00:10:53.500 --> 00:10:55.320 But that’s not important right now. 00:10:55.320 --> 00:10:58.580 But remember, the measurement we took across these two breakers; 00:10:58.580 --> 00:11:02.260 these two right next to each other was 240V. 00:11:02.260 --> 00:11:09.080 If you want to get a 240V circuit out of this panel all you need to do is create a circuit across both bus bars. 00:11:09.080 --> 00:11:12.640 And that’s what these weird double breakers do. 00:11:12.640 --> 00:11:15.040 These are called double-pole breakers. 00:11:15.040 --> 00:11:18.189 When you install one of these in the panel, it takes up two spots 00:11:18.189 --> 00:11:20.480 so that it can access both phases. 00:11:20.480 --> 00:11:23.769 These are actually just two circuit breakers internally bonded together 00:11:23.769 --> 00:11:26.778 so that if one half of it trips, both do. 00:11:26.778 --> 00:11:31.680 In fact, in some cases you can make a 240V circuit with two single-pole breakers 00:11:31.680 --> 00:11:35.200 so long as you bond their trip levers together (and they're the same size). 00:11:35.200 --> 00:11:38.840 To be clear, not all brands or styles of breaker allow you to do that 00:11:38.840 --> 00:11:43.220 and it may or may not be up to code anymore but it is an interesting possible fact! 00:11:43.220 --> 00:11:49.220 And this leads us to another interesting fact; Many of our 240V devices over here are powered 00:11:49.230 --> 00:11:53.120 by two hot wires and no neutral at all. 00:11:53.120 --> 00:11:58.560 You see, the device would only need access to the neutral if it also needs access to 120V. 00:11:58.560 --> 00:12:00.920 Some devices do, but many don’t. 00:12:00.920 --> 00:12:06.300 Now, you might be wondering, how do we actually connect our 240V devices to power? 00:12:06.300 --> 00:12:08.850 Do we have special plugs for that? 00:12:08.850 --> 00:12:09.580 Yes! 00:12:09.580 --> 00:12:12.060 But also, sometimes no! 00:12:12.060 --> 00:12:17.260 Many devices like water heaters or air conditioners are simply directly wired into a circuit. 00:12:17.260 --> 00:12:20.840 Sometimes they’ll go through a service disconnect (which may also have fuses in it) 00:12:20.840 --> 00:12:22.960 depending on the code and the device. 00:12:22.960 --> 00:12:25.120 Some other devices, though, do have plugs. 00:12:25.120 --> 00:12:27.720 We have weird plugs galore over here! 00:12:27.720 --> 00:12:31.160 See this clothes dryer? It’s plugged into this bad boy! 00:12:31.160 --> 00:12:34.420 This 7.2 kW electric vehicle supply equipment? 00:12:34.420 --> 00:12:36.600 It’s got one of these on there! 00:12:36.600 --> 00:12:39.460 Did you catch that the dryer’s plug had four terminals 00:12:39.460 --> 00:12:41.980 but the charging station only had three? 00:12:41.980 --> 00:12:46.360 That’s right, the charging station just has two hots and a ground. 00:12:46.360 --> 00:12:48.800 No neutral connection whatsoever. 00:12:48.800 --> 00:12:51.340 But the dryer has a neutral, too. 00:12:51.340 --> 00:12:55.060 Likely the only thing that actually needs that is the little light bulb inside. 00:12:55.060 --> 00:12:59.160 Or maybe the motor is a 120V motor, the same for a gas-powered dryer 00:12:59.160 --> 00:13:01.900 [hard cut to lo-fi jazz] 00:13:03.480 --> 00:13:05.740 And yes there is a typo on here, of course there is. 00:13:06.080 --> 00:13:09.880 If Premiere could add a basic spell-check to the titling tool that would be fan-friggin-tastic. 00:13:10.760 --> 00:13:12.360 I'll stop with this so you can read that up there ^^ 00:13:23.060 --> 00:13:25.660 but the heating elements obviously need 240. 00:13:25.660 --> 00:13:31.020 But the charging station doesn’t need 120 at all so it just has the two hots. 00:13:31.020 --> 00:13:33.180 Now I’m sure many of you are asking, 00:13:33.180 --> 00:13:35.180 but why do you even do this? 00:13:35.180 --> 00:13:36.640 What’s the point? 00:13:36.640 --> 00:13:38.560 Who is Max Mouse? 00:13:38.560 --> 00:13:42.000 Well, here’s the neat thing about split-phase power. 00:13:42.000 --> 00:13:49.040 Even though we have access to 240V circuits, nowhere in this building (or indeed in this panel) 00:13:49.040 --> 00:13:53.220 will you find a wire with 240V potential on it. 00:13:53.220 --> 00:14:00.180 Except in really bizarre or intentional scenarios, you cannot get an electric shock at 240V potential. 00:14:00.180 --> 00:14:03.320 You have to be touching both hot wires. 00:14:03.320 --> 00:14:09.260 Even in a 240V circuit, the individual wires are only at 120V potential to ground. 00:14:09.260 --> 00:14:13.210 And that makes our electrical system at least somewhat safer. 00:14:13.210 --> 00:14:14.400 I can hear all of you screaming 00:14:14.400 --> 00:14:17.749 “It’s not the voltage that kills you it’s the current flow! 00:14:17.749 --> 00:14:20.920 It’s the volts that jolts but the mils that kills.” 00:14:20.920 --> 00:14:22.120 You’re right. 00:14:22.120 --> 00:14:23.940 But have you considered this; 00:14:23.940 --> 00:14:29.740 with any body of given resistance, the current flowing through it is proportional to the voltage. 00:14:29.740 --> 00:14:33.920 I don’t know if you’ve heard of this little equation, V=I•R 00:14:33.920 --> 00:14:37.220 That’s voltage is equal to current times resistance. 00:14:37.220 --> 00:14:41.180 When you increase voltage, that makes current go up, too! 00:14:41.180 --> 00:14:45.020 And it’s not like American bodies are a lower resistance than yours 00:14:45.020 --> 00:14:47.520 Is 120V “safe?” 00:14:47.520 --> 00:14:49.800 No. Of course not. 00:14:49.800 --> 00:14:54.020 You do not want to come in contact with it and it can still very much kill you. 00:14:54.020 --> 00:14:58.820 But, in any given scenario, if someone is receiving an electric shock 00:14:58.820 --> 00:15:00.540 the voltage matters! 00:15:00.540 --> 00:15:05.740 You will always lower the likelihood of significant injury or death if the voltage is lower. 00:15:05.740 --> 00:15:10.480 There isn’t some magical point at which voltage suddenly becomes dangerous. 00:15:10.480 --> 00:15:14.760 And without enough voltage, your body won’t pass any current at all. 00:15:14.760 --> 00:15:18.000 I mean, take a 12V car battery as an example. 00:15:18.000 --> 00:15:25.300 It can produce literally hundreds of amps; many more amps than my circuit breaker panel can supply. 00:15:25.300 --> 00:15:30.620 But 12V is not enough pressure to send any of that current into your body 00:15:30.620 --> 00:15:36.020 except in really weird circumstances like electrodes piercing your skin. 00:15:36.020 --> 00:15:40.600 People get really hung up whenever I’ve mentioned that 120V is safer because I guess 00:15:40.610 --> 00:15:43.460 they think I’m saying it’s safe? 00:15:43.460 --> 00:15:46.780 I dunno. I’ll be clear, it’s not safe! 00:15:46.780 --> 00:15:47.580 And in fairness, 00:15:47.580 --> 00:15:54.500 any safety benefit we might get from it is obviously negated by the fact that our plugs are so terrible. 00:15:54.500 --> 00:15:57.240 I mean, the entire pin’s length is conductive. 00:15:57.240 --> 00:16:00.480 You’re just asking for a shock when you plug anything in. 00:16:00.480 --> 00:16:02.840 It literally just takes holding it wrong. 00:16:02.840 --> 00:16:05.120 And these big plugs are even worse! 00:16:05.120 --> 00:16:10.019 Plus, we have dumb-as-rocks circuit breakers in most homes and only put 00:16:10.019 --> 00:16:14.100 leakage current detection devices in bathrooms and kitchens, so yeah. 00:16:14.100 --> 00:16:19.480 We have way more opportunities to be shocked, and that is itself a huge problem. 00:16:19.480 --> 00:16:22.960 But, it doesn’t negate the fact that, all else being equal - 00:16:22.960 --> 00:16:24.680 and please understand what I mean by that; 00:16:24.680 --> 00:16:28.720 in any given scenario where one is receiving an electric shock 00:16:28.720 --> 00:16:34.320 - a 240V shock is unquestionably worse than a 120V one. 00:16:34.320 --> 00:16:39.080 Yes, 120V is still very dangerous! It can still kill you! You still want to not be shocked! 00:16:39.080 --> 00:16:41.220 That is priority one. 00:16:41.220 --> 00:16:45.960 But it is at least marginally safer all else being equal. 00:16:45.960 --> 00:16:49.820 Now to be clear, it’s not just for safety that we’ve done this. 00:16:49.820 --> 00:16:53.420 In fact, likely that’s just a happy accident of our history 00:16:53.420 --> 00:16:55.720 going back to the AC/DC wars. [metal music plays under AC/DC] 00:16:55.720 --> 00:17:01.589 And for what it’s worth we never had quite the hardship finding raw materials for building wiring 00:17:01.589 --> 00:17:07.540 so the thicker cabling required for 120V circuitry generally wasn’t a huge consideration. 00:17:07.540 --> 00:17:12.540 Meanwhile in much of Europe the savings allowed by using 240V were substantial 00:17:12.540 --> 00:17:14.800 especially in the wake of World War II. 00:17:14.800 --> 00:17:17.600 And then there are the ring mains of the UK. 00:17:17.600 --> 00:17:19.400 Look those up if you've never heard of them. 00:17:19.400 --> 00:17:21.120 They’re weird. 00:17:21.120 --> 00:17:26.920 And, fun fact, in the UK they actually use split-phase power on construction sites! 00:17:26.920 --> 00:17:31.240 In that case, the potential across the two wires is 110V funnily enough, 00:17:31.240 --> 00:17:35.040 with each wire only at 55V potential to ground. 00:17:35.040 --> 00:17:38.140 This is done for the express purpose of increasing safety! 00:17:38.140 --> 00:17:41.140 55V is even more safe than 120. 00:17:41.140 --> 00:17:44.840 55V is barely above what power other Ethernet is. 00:17:44.840 --> 00:17:51.180 Anyway, since the stuff used on the construction sites is wired across the phases, it all runs at 110V. 00:17:51.180 --> 00:17:54.740 So I guess a fair number of UK power tools can be used over here. 00:17:54.740 --> 00:17:56.080 Whaddya know. 00:17:56.080 --> 00:18:00.840 Yeah - quick note, for some reason lots of people will refer to our voltage as 110V 00:18:00.840 --> 00:18:02.740 (and thus 110/220) 00:18:02.740 --> 00:18:07.280 or maybe 117 or 115 or even 125. 00:18:07.280 --> 00:18:10.340 OK, to those of you who do that, just… 00:18:10.340 --> 00:18:11.520 it’s 120. 00:18:11.520 --> 00:18:15.840 But there is no concrete exact voltage to any electric grid. 00:18:15.840 --> 00:18:21.040 It varies depending on conditions so everything operates within a range of acceptable voltages. 00:18:21.040 --> 00:18:26.900 Usually here I get something like 123V but in other places you might only have 115V. 00:18:26.900 --> 00:18:30.720 Or maybe even 110. It’s fine, stop being pedantic about it. 00:18:30.720 --> 00:18:34.700 Anyway, that’s all I really wanted to share with this video. A basic overview of the US 00:18:34.700 --> 00:18:39.620 electrical system so everyone is clear on the fact we have 240V power. 00:18:39.620 --> 00:18:42.900 It’s a little weird, but it’s there and we do use it. 00:18:42.900 --> 00:18:44.900 It’s not like we’re in the dark ages. 00:18:44.900 --> 00:18:50.520 Oh right, and wait, that thing about the fact that this is a single family home being important! 00:18:50.520 --> 00:18:51.140 Ah! 00:18:51.140 --> 00:18:56.900 Recently I made a video about fans and motors and how single phase power makes motors hard. 00:18:56.909 --> 00:19:02.400 Well, in that video I talked about how in an apartment building you might have 208V power 00:19:02.400 --> 00:19:04.840 rather than "the standard 240." 00:19:04.840 --> 00:19:06.820 That seemed to confuse a lot of people, 00:19:06.820 --> 00:19:11.812 especially those of you who until right now didn’t know that we have standard 240! 00:19:11.812 --> 00:19:15.580 Apartments often have 208v in their service panels 00:19:15.580 --> 00:19:19.620 because many larger buildings are hooked up to a three-phase power supply. 00:19:19.620 --> 00:19:22.840 When done in the most common Wye (Y) configuration, 00:19:22.840 --> 00:19:30.360 each phase is 120V respective to neutral, but across any two phases you have 208 volts. 00:19:30.360 --> 00:19:35.679 In those buildings, your electrical panel will be extremely similar to that of a single-family home. 00:19:35.679 --> 00:19:38.420 There will be two hot phases as well as a neutral. 00:19:38.420 --> 00:19:42.600 But, those two hot phases are not from a split-phase transformer, 00:19:42.600 --> 00:19:47.720 but are in fact two of three available phases from a three phase transformer. 00:19:47.720 --> 00:19:54.220 And it’s the difference in phase angle, 120 degrees versus 180, that makes the potential across the phases 00:19:54.220 --> 00:19:56.800 208V and not 240V. 00:19:56.800 --> 00:19:59.120 It’s actually geometry! In a way. 00:19:59.120 --> 00:20:01.000 Or is it trigonometry? Whatever. 00:20:01.000 --> 00:20:07.600 Most of our devices which are designed to operate on 240V will happily operate on 208V as well. 00:20:07.600 --> 00:20:12.929 In fact, they’ll often specifically have labels on them that say 240V / 208V. 00:20:12.929 --> 00:20:19.380 The only real downside of 208 is that devices which produce heat will only produce 86.7% 00:20:19.380 --> 00:20:22.000 of what they would on a 240V circuit. 00:20:22.000 --> 00:20:28.380 So, if you live in an apartment building, your stove will be just slightly less hot than it might otherwise be. 00:20:28.380 --> 00:20:31.880 Or, if you have an electric vehicle charging station installed on 208, 00:20:31.880 --> 00:20:37.169 it will charge slightly slower than it would on 240. But, not a big deal. 00:20:37.169 --> 00:20:42.860 Thanks for watching! I hope you enjoyed this and, if you didn’t know this about the US, have been enlightened. 00:20:42.860 --> 00:20:47.040 And will stop badgering me about only having 120V. 00:20:47.040 --> 00:20:51.340 Just about the only way we’re held back by our weedy little outlets 00:20:51.340 --> 00:20:53.860 is portable things that make heat. 00:20:53.860 --> 00:20:56.600 Yes, our kettles and pretty much everything are capped 00:20:56.600 --> 00:21:02.700 at 1.5 kilowatts for an 80% safety margin on a 15A circuit, but really… 00:21:02.700 --> 00:21:07.940 aside from space heaters and tea kettles nothing is worse for being capped at 1500 watts. 00:21:07.940 --> 00:21:10.500 And when we need more than that we have options. 00:21:10.500 --> 00:21:12.380 We always had. 00:21:12.380 --> 00:21:16.980 Yes, our electrical system is very very flawed and our receptacles do just suck. 00:21:16.980 --> 00:21:20.780 Really they’re awful. They’re just terribly unsafe. 00:21:20.780 --> 00:21:23.920 But; specifically to Brits and Australians - 00:21:23.920 --> 00:21:27.520 your obsession with switches on receptacles makes no sense to me. 00:21:27.520 --> 00:21:33.700 I’ve received many befuddled comments wondering how we’re supposed to turn things off without unplugging them. 00:21:33.700 --> 00:21:39.380 Well, first, all of our stuff from vacuum cleaners to toaster ovens has its own power switch. 00:21:39.380 --> 00:21:41.560 Like - do you just not have that? 00:21:41.560 --> 00:21:44.860 Do companies design stuff for you assuming you’ve got that little switch? 00:21:44.860 --> 00:21:47.580 Because that’s not my problem. That’s your problem. 00:21:47.580 --> 00:21:53.340 Yes we leave stuff plugged in all the time but other than electronics stuff it’s not consuming any power at all! 00:21:53.340 --> 00:21:57.380 I remember one comment I read saying that the fact our outlets don’t have switches on them 00:21:57.380 --> 00:22:00.600 must be "yet another sign of us being wasteful Americans." 00:22:00.600 --> 00:22:01.600 [inhales exasperatedly] 00:22:01.600 --> 00:22:06.480 No. There are many many signs of that but this isn’t one of them. 00:22:06.480 --> 00:22:09.610 You will never convince me that your switches on sockets 00:22:09.610 --> 00:22:12.420 are anything other than a mild convenience. 00:22:12.420 --> 00:22:16.080 And for what it’s worth, we put switches on our power strips 00:22:16.080 --> 00:22:21.460 so we have that option for addressing electronics with standby lights and vampire drains. 00:22:21.460 --> 00:22:23.140 Oh but what about safety? 00:22:23.140 --> 00:22:24.560 My rebuttal? 00:22:24.560 --> 00:22:26.200 Just unplug the thing! 00:22:26.200 --> 00:22:30.180 You had to reach for the socket anyway to flip that switch. 00:22:30.180 --> 00:22:32.820 It’s not my problem your plugs are so awkward. 00:22:32.820 --> 00:22:35.040 And no, sparking is not dangerous. 00:22:35.040 --> 00:22:38.220 A spark from inrush current won’t hurt anything. 00:22:38.220 --> 00:22:41.780 Really, some of you seem so scared of various electricity things. 00:22:41.780 --> 00:22:42.460 I don’t get it. 00:22:42.460 --> 00:22:44.080 I mean, shaver sockets? 00:22:44.080 --> 00:22:45.020 Really? 00:22:45.020 --> 00:22:47.600 Just put an RCD in the bathroom. 00:22:47.600 --> 00:22:51.240 And for being so afraid of that your electric showers are baffling. 00:22:51.240 --> 00:22:53.570 Really, I know our electrical system has its flaws 00:22:53.570 --> 00:22:57.940 but your perception of how dangerous electricity is seems really out of whack. 00:22:57.940 --> 00:22:59.140 And ring mains? 00:22:59.140 --> 00:23:01.240 Really? What year is it? 00:23:01.240 --> 00:23:04.700 Now, to be fair your fuses in the plug; that's pretty cool. 00:23:04.700 --> 00:23:05.980 I’ll give you that. 00:23:05.980 --> 00:23:08.000 Though they do seem like quite a foot hazard. 00:23:08.000 --> 00:23:09.080 I guess, which is worse? 00:23:09.080 --> 00:23:12.760 Shock hazard from 120V or foot hazard from UK plugs? [music fades in] 00:23:12.760 --> 00:23:14.300 Someone should do a study... 00:23:14.300 --> 00:23:18.160 Anyway, I really think that you guys just need to chill out over there, electricity’s not gonna kill you 00:23:18.160 --> 00:23:19.260 it’ll be fine… 00:23:20.100 --> 00:23:22.680 ♫ electrifyingly smooth jazz ♫ 00:23:23.880 --> 00:23:27.560 That’s what you'll find in most countries around the world when deal…. Ooh. 00:23:28.780 --> 00:23:29.920 [exhales exasperatedly] 00:23:30.280 --> 00:23:33.800 To get that full potenti… oh shoot, that’s not the end of the sentence. 00:23:33.800 --> 00:23:38.720 But you have to be across those two cables, not just across one of them and neutral [stops] 00:23:38.720 --> 00:23:40.800 To get… mahhhh [as he realized he stopped mid-sentence] 00:23:40.800 --> 00:23:43.940 And it can still very much kill you, but…. 00:23:43.940 --> 00:23:46.340 Oh... Yeah, that’s not how the line’s written. 00:23:46.340 --> 00:23:49.780 ...terminal… this other bit is just to…. 00:23:49.960 --> 00:23:53.000 [stares befuddledly at the circuit breaker] 00:23:53.640 --> 00:23:55.640 Yeah I got that backwards! I lost… 00:23:55.640 --> 00:23:58.520 I lost, I already lost track of which side is which. 00:23:58.520 --> 00:24:01.480 Which one is which? Ii is…. 00:24:01.480 --> 00:24:03.160 This side. 00:24:03.160 --> 00:24:06.540 Yes. Our kettles and space heaters… 00:24:07.480 --> 00:24:08.340 Oh... 00:24:09.400 --> 00:24:13.420 I don't want to see another *laughs in 240V* comment on the internet, OK? 00:24:13.420 --> 00:24:15.820 All y'all better have learned now. 00:24:15.820 --> 00:24:20.360 And, by the way, I timed my 120V tea kettle. 2:30 to boil 750 mL of water. 00:24:20.360 --> 00:24:24.920 If that ain't fast enough y'all are wicked impatient.