1
00:00:00,110 --> 00:00:04,180
This video has had something like seventeen
false starts.

2
00:00:04,180 --> 00:00:08,060
I’ve gone down a number of rabbit holes trying to understand a bunch of things,

3
00:00:08,060 --> 00:00:12,500
and I had at one point committed to making an entirely different video because of that!

4
00:00:12,500 --> 00:00:15,269
But then I ran into a number of conceptual hurdles

5
00:00:15,269 --> 00:00:17,120
that I don’t have the energy to
address right now

6
00:00:17,120 --> 00:00:20,700
so we’re back to the simple scope of that first one.

7
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

8
00:00:24,970 --> 00:00:28,560
I have with how the rest of the world seems
to understand the United States

9
00:00:28,560 --> 00:00:31,380
(and more broadly North American)
electrical system.

10
00:00:31,380 --> 00:00:36,280
While it’s true that we have terrible, barely adequate receptacle designs

11
00:00:36,280 --> 00:00:38,500
and our kettles are slower
than yours,

12
00:00:38,500 --> 00:00:42,380
here’s a fact about us that I think will blow a few fuses out there;

13
00:00:42,380 --> 00:00:45,930
The US is a 240 volt country.

14
00:00:45,930 --> 00:00:47,220
I can hear a lot of you going

15
00:00:47,220 --> 00:00:48,140
whaaaa????
[with obnoxious buzzing and other sound effects added]

16
00:00:48,140 --> 00:00:49,360
But it’s true!

17
00:00:49,360 --> 00:00:53,820
We have 240V in our electrical panels and at our disposal.

18
00:00:53,820 --> 00:00:56,720
You’ve heard about our obsession with air conditioning, right?

19
00:00:56,720 --> 00:01:00,710
Did you really think we’re cooling
our gaudy McMansions with a machine we just

20
00:01:00,710 --> 00:01:02,740
plug into a regular outlet?

21
00:01:02,740 --> 00:01:03,600
No.

22
00:01:03,600 --> 00:01:05,280
And some of us have electric stoves,

23
00:01:05,280 --> 00:01:06,340
electric water heaters,

24
00:01:06,340 --> 00:01:07,240
clothes dryers,

25
00:01:07,240 --> 00:01:09,880
and even electric vehicle
charging now!

26
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).

27
00:01:15,520 --> 00:01:17,020
How are we doing it, then?

28
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.

29
00:01:21,260 --> 00:01:24,240
[electrical humming]
Here’s a standard US service panel we can look at!

30
00:01:24,240 --> 00:01:25,760
It might be a little hard to hear --

31
00:01:25,760 --> 00:01:27,260
[humming abruptly stops]
I'm just kidding.

32
00:01:27,260 --> 00:01:29,640
I added that 60 Hz hum in post.

33
00:01:29,640 --> 00:01:33,880
Did you seriously think our service panels are some sort of disastrously loud thing?

34
00:01:33,880 --> 00:01:35,240
I bet some of you did.

35
00:01:35,660 --> 00:01:38,340
Anyway, this building is a single family home.

36
00:01:38,340 --> 00:01:41,580
That’s important because of a little
thing I’ll be bringing up later.

37
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

38
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

39
00:01:52,180 --> 00:01:54,980
are the work of yours truly but, again - not important!

40
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

41
00:02:01,020 --> 00:02:04,880
an absurd number of circuit breakers feeding
individual circuits.

42
00:02:04,880 --> 00:02:07,740
But there’s still room for two more!

43
00:02:07,740 --> 00:02:10,700
The main breaker is a 200 amp breaker.

44
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.

45
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.

46
00:02:22,560 --> 00:02:27,100
But no, that’s 200 amps at 240 volts, so in fact

47
00:02:27,100 --> 00:02:30,100
many homes have 48 kW to go around.

48
00:02:30,100 --> 00:02:34,100
100A service is still fairly common but that’s still 24 kW.

49
00:02:34,100 --> 00:02:38,960
Plenty for smaller homes, especially
since natural gas or other types of fuel combustion

50
00:02:38,960 --> 00:02:42,520
for space heating is still quite common ‘round these
parts.

51
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

52
00:02:47,000 --> 00:02:50,560
and you’ll also see that
a few of them are… weird.

53
00:02:51,160 --> 00:02:53,400
They take up two spaces for some reason.

54
00:02:53,940 --> 00:02:54,840
Huh.

55
00:02:55,120 --> 00:02:57,740
Well, those are 240V circuits.

56
00:02:57,740 --> 00:03:02,020
This one’s going to a clothes dryer, this one to an air conditioner, etc.

57
00:03:02,020 --> 00:03:04,080
But… why two spaces?

58
00:03:04,080 --> 00:03:06,240
That seems a little weird, doesn’t it?

59
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.

60
00:03:11,640 --> 00:03:16,120
You see our power transformers that
feed our homes do produce 120V.

61
00:03:16,440 --> 00:03:17,720
But twice!

62
00:03:18,060 --> 00:03:22,460
Yeah! It’s weird! But first, a quick reminder
of what transformers do;

63
00:03:22,460 --> 00:03:24,160
They’re more than meets the eye.

64
00:03:24,160 --> 00:03:28,349
Pretty much THE reason we use
AC power all over the place is that we can

65
00:03:28,349 --> 00:03:31,840
use transformers to step the voltage up and
down all will nilly.

66
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

67
00:03:36,730 --> 00:03:40,630
which propogates through it! Then, wrap some
more wires around the core on the other side

68
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

69
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!

70
00:03:49,960 --> 00:03:50,920
It’s pretty neat!

71
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.

72
00:03:56,400 --> 00:03:59,720
That lets those wires carry a ton of power for their size,

73
00:03:59,720 --> 00:04:03,230
because while the cross-sectional
area of any given conductor affects how much

74
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

75
00:04:08,909 --> 00:04:13,880
(that’s watts) with the same amount of current
and thus a relatively small cable.

76
00:04:13,880 --> 00:04:19,160
This allows us to transmit power over long distances economically in the near megavolt range.

77
00:04:19,160 --> 00:04:24,540
Substations will step that down to a more reasonable 11 or maybe 32 *thousand* volts

78
00:04:24,540 --> 00:04:26,050
for neighborhood distribution,

79
00:04:26,050 --> 00:04:30,669
and right before it enters your home it is
stepped down by a final transformer which

80
00:04:30,669 --> 00:04:34,420
delivers the final, relatively low voltage
to your home.

81
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

82
00:04:39,110 --> 00:04:41,260
the transformer and call it a day.

83
00:04:41,260 --> 00:04:43,600
That’s what you’ll find in most countries around the world

84
00:04:43,600 --> 00:04:46,420
when dealing with standard single-phase
electric service.

85
00:04:46,420 --> 00:04:48,720
[whispers]
We’re just gonna ignore three-phase for 
right now.

86
00:04:48,720 --> 00:04:52,599
The secondary
winding produces a 240V potential and thus

87
00:04:52,599 --> 00:04:55,480
you get 240V out of that transformer.

88
00:04:55,480 --> 00:05:00,720
And believe it or not, that’s exactly what our transformers do!

89
00:05:00,720 --> 00:05:05,860
They produce 240V on the
secondary winding, just like yours.

90
00:05:05,860 --> 00:05:07,740
But the weird bit is that

91
00:05:07,740 --> 00:05:09,600
This is America.

92
00:05:09,600 --> 00:05:13,520
We’re not gonna settle for hooking up a measly two wires to our transformers.

93
00:05:13,520 --> 00:05:15,560
That is simply unamerican.

94
00:05:15,560 --> 00:05:18,060
No, we must have three.

95
00:05:18,060 --> 00:05:20,560
That’s one more and thus better.

96
00:05:20,560 --> 00:05:21,860
Obviously.

97
00:05:22,349 --> 00:05:24,440
This is where the weirdness happens!

98
00:05:24,440 --> 00:05:28,680
Our transformers don’t just have taps on the ends of the secondary winding.

99
00:05:28,680 --> 00:05:32,440
We put a third, central
tap right smack dab in the middle,

100
00:05:32,440 --> 00:05:35,088
or center, of that winding in its middle.

101
00:05:35,088 --> 00:05:38,180
And that center tap becomes referenced to Earth,

102
00:05:38,180 --> 00:05:40,560
and that is what defines our neutral.

103
00:05:40,560 --> 00:05:43,860
Doing this creates
what is called split-phase power.

104
00:05:43,860 --> 00:05:48,280
We end up with what behaves as though there are two 120V potentials

105
00:05:48,280 --> 00:05:51,500
180 degrees out of phase from one another.

106
00:05:51,500 --> 00:05:55,540
Across either of those and neutral
you get 120V,

107
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.

108
00:06:01,980 --> 00:06:04,267
So now let’s go back to the electrical panel.

109
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.

110
00:06:08,420 --> 00:06:09,920
This is the part where I say

111
00:06:09,920 --> 00:06:11,960
Don't Try This At Home!

112
00:06:11,960 --> 00:06:16,560
There are many things inside this
box that can kill you if you touch them.

113
00:06:16,560 --> 00:06:20,040
I have a fairly good understanding of what those
dangers are in here;

114
00:06:20,040 --> 00:06:23,800
good enough to run a few new circuits without injuring myself or burning the house down

115
00:06:23,800 --> 00:06:26,300
with, so far, a 100% success rate.

116
00:06:26,300 --> 00:06:29,220
But this is not something to
play around with.

117
00:06:29,220 --> 00:06:32,140
I’m showing you mine so you don’t need to see yours.

118
00:06:32,140 --> 00:06:32,930
Kay?

119
00:06:32,930 --> 00:06:35,800
Alright. Here’s where the magic happens.

120
00:06:35,800 --> 00:06:39,860
I know, to those of you in Europe this looks horribly gross and terribly unsafe but

121
00:06:39,860 --> 00:06:42,160
that’s OK. We're coping.

122
00:06:42,160 --> 00:06:46,480
Up at the top there are three beefy cables coming in.

123
00:06:46,480 --> 00:06:50,660
Those come from the meter box outside but
ultimately from the transformer.

124
00:06:50,660 --> 00:06:55,520
The two outer cables are both live at 120V potential to
ground.

125
00:06:55,520 --> 00:06:58,260
The middle cable is, conveniently,

126
00:06:58,260 --> 00:07:01,000
ground. And also neutral!

127
00:07:01,000 --> 00:07:04,699
Yes. That middle
cable is connected to a ground rod outside

128
00:07:04,699 --> 00:07:09,200
by the meter box, in addition to being connected
to the center tap of the transformer.

129
00:07:09,200 --> 00:07:13,220
For those that didn’t know this already, the
ground plug and the neutral plug

130
00:07:13,220 --> 00:07:18,340
of your electrical outlets usually end up in the same exact place eventually.

131
00:07:18,340 --> 00:07:19,400
Right here!

132
00:07:19,400 --> 00:07:20,700
(and on the other side)

133
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

134
00:07:24,780 --> 00:07:26,389
and there are particular exceptions

135
00:07:26,389 --> 00:07:29,080
so we’re just avoiding that whole can of
worms.

136
00:07:29,080 --> 00:07:32,000
If I take a voltage measurement between this cable and the neutral,

137
00:07:32,000 --> 00:07:34,820
you’ll see that it’s 120 volts (or thereabouts).

138
00:07:34,820 --> 00:07:39,580
If I measure from the other cable to neutral it is also 120 something volts.

139
00:07:39,580 --> 00:07:44,680
Remember those two pairs
of cables are across only half of the transformer.

140
00:07:44,680 --> 00:07:48,100
Conveniently they end up in the panel in that
same orientation.

141
00:07:48,100 --> 00:07:50,360
This is the left side of the secondary winding.

142
00:07:50,360 --> 00:07:51,760
The right side of the secondary.

143
00:07:51,760 --> 00:07:53,980
And the center tap of the secondary.

144
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.

145
00:08:00,440 --> 00:08:06,960
But across those two outer cables you do in
fact get 240V. Or close, anyway.

146
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.

147
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,

148
00:08:17,300 --> 00:08:19,040
to get the full potential.

149
00:08:19,040 --> 00:08:24,380
And that’s why our 240V circuits are on these weird double breakers.

150
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.

151
00:08:30,159 --> 00:08:34,399
A circuit breaker makes contact with that
bus bar and provides an internal link to an

152
00:08:34,399 --> 00:08:36,740
output on a screw terminal.

153
00:08:36,740 --> 00:08:39,120
The breaker can interrupt the current path from the bus bar

154
00:08:39,120 --> 00:08:42,340
to the terminal either manually with the toggle

155
00:08:42,340 --> 00:08:44,540
[two clicks as it is actuated)

156
00:08:44,540 --> 00:08:47,800
or automatically in the case of an overcurrent event.

157
00:08:47,800 --> 00:08:51,040
This here is all a typical US circuit breaker is.

158
00:08:51,040 --> 00:08:51,580
[click]

159
00:08:51,580 --> 00:08:52,440
[clack]

160
00:08:52,440 --> 00:08:55,940
It’s attached only to the live or hot side of the circuit.

161
00:08:55,940 --> 00:08:59,400
The neutral side of any circuit
goes directly back to the panel.

162
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

163
00:09:04,330 --> 00:09:06,840
bus bars that the breaker will attach to.

164
00:09:06,840 --> 00:09:09,279
On the bottom of the breaker, this contact

165
00:09:09,280 --> 00:09:14,240
will clamp onto the bus bar, which through
the switch contacts inside the breaker eventually

166
00:09:14,240 --> 00:09:16,680
make it to the output terminal here.

167
00:09:16,680 --> 00:09:19,480
The other
bit is just to physically attach the breaker

168
00:09:19,480 --> 00:09:23,500
to the panel more sturdily via this plastic
peg thing.

169
00:09:23,500 --> 00:09:26,700
The bus bars, though, aren’t just going
straight down the panel.

170
00:09:26,700 --> 00:09:29,580
They’re a sort of interlocking comb shape.

171
00:09:29,580 --> 00:09:33,250
What this does is make it so that every alternate position

172
00:09:33,250 --> 00:09:37,520
down the panel is being fed by the opposite
lug up there.

173
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,

174
00:09:42,060 --> 00:09:44,040
and the other is connected to the left.

175
00:09:44,040 --> 00:09:47,680
Now, if you take a look at these
two circuit breakers, they’re both feeding

176
00:09:47,680 --> 00:09:50,180
their own 120V circuits.

177
00:09:50,180 --> 00:09:54,649
But they aren’t
themselves fed by the same cable up top.

178
00:09:54,649 --> 00:09:58,840
Take a look - across these two breakers there’s
actually 240V.

179
00:09:58,840 --> 00:10:02,880
That’s because one breaker is attached to this cable through the bus bar.

180
00:10:02,880 --> 00:10:04,220
(I'm pointing to the left one)

181
00:10:04,220 --> 00:10:07,320
And the other one is attached to the other.
(that's the right one)

182
00:10:07,320 --> 00:10:11,460
Again, each one of these breakers is feeding
a different circuit.

183
00:10:11,460 --> 00:10:14,520
If you follow the wire coming out from the breaker,

184
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.

185
00:10:20,280 --> 00:10:23,960
Those cables; they go to the various circuits in the building

186
00:10:23,960 --> 00:10:26,540
(or rather they are the various circuits of the building)

187
00:10:26,540 --> 00:10:29,819
and in the 120V circuits across the black hot wire

188
00:10:29,819 --> 00:10:32,960
and the white neutral wire you have 120V.

189
00:10:32,960 --> 00:10:36,160
The circuit breaker
is there mostly to protect the circuit from

190
00:10:36,160 --> 00:10:41,259
being overloaded and damaging the conductors,
or worse, starting a fire. But in conjunction

191
00:10:41,259 --> 00:10:46,420
with a grounded appliance it will also remove
voltage should the 120V potential come in

192
00:10:46,420 --> 00:10:50,990
contact with the grounded casing because that
effectively becomes a dead short which will

193
00:10:50,990 --> 00:10:53,500
trip the breaker more or less instantly.

194
00:10:53,500 --> 00:10:55,320
But that’s not important right now.

195
00:10:55,320 --> 00:10:58,580
But remember, the measurement we took across
these two breakers;

196
00:10:58,580 --> 00:11:02,260
these two right next to each other was 240V.

197
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.

198
00:11:09,080 --> 00:11:12,640
And that’s what these weird double
breakers do.

199
00:11:12,640 --> 00:11:15,040
These are called double-pole breakers.

200
00:11:15,040 --> 00:11:18,189
When you install one
of these in the panel, it takes up two spots

201
00:11:18,189 --> 00:11:20,480
so that it can access both phases.

202
00:11:20,480 --> 00:11:23,769
These are actually
just two circuit breakers internally bonded together

203
00:11:23,769 --> 00:11:26,778
so that if one half of it trips, both do.

204
00:11:26,778 --> 00:11:31,680
In fact, in some cases you can make a 240V circuit with two single-pole breakers

205
00:11:31,680 --> 00:11:35,200
so long as you bond their trip levers together (and they're the same size).

206
00:11:35,200 --> 00:11:38,840
To be clear, not all brands or styles of breaker
allow you to do that

207
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!

208
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

209
00:11:49,230 --> 00:11:53,120
by two hot wires and no neutral at all.

210
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.

211
00:11:58,560 --> 00:12:00,920
Some devices do, but many don’t.

212
00:12:00,920 --> 00:12:06,300
Now, you might be wondering, how do we actually connect our 240V devices to power?

213
00:12:06,300 --> 00:12:08,850
Do we have special plugs for that?

214
00:12:08,850 --> 00:12:09,580
Yes!

215
00:12:09,580 --> 00:12:12,060
But also, sometimes no!

216
00:12:12,060 --> 00:12:17,260
Many devices like water heaters or air conditioners are simply directly wired into a circuit.

217
00:12:17,260 --> 00:12:20,840
Sometimes they’ll go through a service disconnect (which may also have fuses in it)

218
00:12:20,840 --> 00:12:22,960
depending on the code and the device.

219
00:12:22,960 --> 00:12:25,120
Some other devices, though, do have plugs.

220
00:12:25,120 --> 00:12:27,720
We have weird plugs
galore over here!

221
00:12:27,720 --> 00:12:31,160
See this clothes dryer? It’s plugged into this bad boy!

222
00:12:31,160 --> 00:12:34,420
This 7.2 kW electric vehicle
supply equipment?

223
00:12:34,420 --> 00:12:36,600
It’s got one of these on there!

224
00:12:36,600 --> 00:12:39,460
Did you catch that the dryer’s plug had
four terminals

225
00:12:39,460 --> 00:12:41,980
but the charging station only had three?

226
00:12:41,980 --> 00:12:46,360
That’s right, the charging station
just has two hots and a ground.

227
00:12:46,360 --> 00:12:48,800
No neutral connection whatsoever.

228
00:12:48,800 --> 00:12:51,340
But the dryer has a neutral, too.

229
00:12:51,340 --> 00:12:55,060
Likely the only thing that actually needs that is the little light bulb inside.

230
00:12:55,060 --> 00:12:59,160
Or maybe the motor is a 120V motor, the same for a gas-powered dryer

231
00:12:59,160 --> 00:13:01,900
[hard cut to lo-fi jazz]

232
00:13:03,480 --> 00:13:05,740
And yes there is a typo on here, of course there is.

233
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.

234
00:13:10,760 --> 00:13:12,360
I'll stop with this so you can read that up there ^^

235
00:13:23,060 --> 00:13:25,660
but the heating elements obviously need 240.

236
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.

237
00:13:31,020 --> 00:13:33,180
Now I’m sure many of you are asking,

238
00:13:33,180 --> 00:13:35,180
but why do you even do this?

239
00:13:35,180 --> 00:13:36,640
What’s the point?

240
00:13:36,640 --> 00:13:38,560
Who is Max Mouse?

241
00:13:38,560 --> 00:13:42,000
Well, here’s the neat
thing about split-phase power.

242
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)

243
00:13:49,040 --> 00:13:53,220
will you find a wire with 240V potential on it.

244
00:13:53,220 --> 00:14:00,180
Except in really bizarre or intentional scenarios, you cannot get an electric shock at 240V potential.

245
00:14:00,180 --> 00:14:03,320
You have to be touching both hot wires.

246
00:14:03,320 --> 00:14:09,260
Even in a 240V circuit, the individual wires are only at 120V potential to ground.

247
00:14:09,260 --> 00:14:13,210
And that makes our electrical
system at least somewhat safer.

248
00:14:13,210 --> 00:14:14,400
I can hear all of you screaming

249
00:14:14,400 --> 00:14:17,749
“It’s not the voltage that kills you it’s the current flow!

250
00:14:17,749 --> 00:14:20,920
It’s the volts that jolts but the
mils that kills.”

251
00:14:20,920 --> 00:14:22,120
You’re right.

252
00:14:22,120 --> 00:14:23,940
But have you considered this;

253
00:14:23,940 --> 00:14:29,740
with any body of given resistance, the current flowing through it is proportional to the voltage.

254
00:14:29,740 --> 00:14:33,920
I don’t know if you’ve heard of this little equation, 
V=I•R

255
00:14:33,920 --> 00:14:37,220
That’s voltage is equal
to current times resistance.

256
00:14:37,220 --> 00:14:41,180
When you increase voltage, that makes current go up, too!

257
00:14:41,180 --> 00:14:45,020
And it’s not like American bodies are a lower resistance than yours

258
00:14:45,020 --> 00:14:47,520
Is 120V “safe?”

259
00:14:47,520 --> 00:14:49,800
No. Of course not.

260
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.

261
00:14:54,020 --> 00:14:58,820
But, in any given scenario, if someone is receiving an electric shock

262
00:14:58,820 --> 00:15:00,540
the voltage matters!

263
00:15:00,540 --> 00:15:05,740
You will always lower the likelihood of significant injury or death if the voltage is lower.

264
00:15:05,740 --> 00:15:10,480
There isn’t some magical point at which voltage suddenly becomes dangerous.

265
00:15:10,480 --> 00:15:14,760
And without enough voltage, your body won’t pass any current at all.

266
00:15:14,760 --> 00:15:18,000
I mean, take a 12V car battery as an example.

267
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.

268
00:15:25,300 --> 00:15:30,620
But 12V is not enough pressure to
send any of that current into your body

269
00:15:30,620 --> 00:15:36,020
except in really weird circumstances like electrodes
piercing your skin.

270
00:15:36,020 --> 00:15:40,600
People get really hung up whenever I’ve
mentioned that 120V is safer because I guess

271
00:15:40,610 --> 00:15:43,460
they think I’m saying it’s safe?

272
00:15:43,460 --> 00:15:46,780
I dunno.
I’ll be clear, it’s not safe!

273
00:15:46,780 --> 00:15:47,580
And in fairness,

274
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.

275
00:15:54,500 --> 00:15:57,240
I mean, the entire pin’s length
is conductive.

276
00:15:57,240 --> 00:16:00,480
You’re just asking for a shock when you plug anything in.

277
00:16:00,480 --> 00:16:02,840
It literally just takes holding it wrong.

278
00:16:02,840 --> 00:16:05,120
And these big plugs are even worse!

279
00:16:05,120 --> 00:16:10,019
Plus, we have dumb-as-rocks
circuit breakers in most homes and only put

280
00:16:10,019 --> 00:16:14,100
leakage current detection devices in bathrooms
and kitchens, so yeah.

281
00:16:14,100 --> 00:16:19,480
We have way more opportunities to be shocked, and that is itself a huge problem.

282
00:16:19,480 --> 00:16:22,960
But, it doesn’t negate the fact that, all else being equal -

283
00:16:22,960 --> 00:16:24,680
and please understand what I mean by that;

284
00:16:24,680 --> 00:16:28,720
in any given scenario where one is receiving an electric shock

285
00:16:28,720 --> 00:16:34,320
- a 240V shock is unquestionably worse than a 120V one.

286
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!

287
00:16:39,080 --> 00:16:41,220
That is priority one.

288
00:16:41,220 --> 00:16:45,960
But it is at least marginally
safer all else being equal.

289
00:16:45,960 --> 00:16:49,820
Now to be clear, it’s not just for safety
that we’ve done this.

290
00:16:49,820 --> 00:16:53,420
In fact, likely that’s just a happy accident of our history

291
00:16:53,420 --> 00:16:55,720
going back to the AC/DC wars.
[metal music plays under AC/DC]

292
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

293
00:17:01,589 --> 00:17:07,540
so the thicker cabling required for 120V circuitry generally wasn’t a huge consideration.

294
00:17:07,540 --> 00:17:12,540
Meanwhile in much of Europe the savings allowed by using 240V were substantial

295
00:17:12,540 --> 00:17:14,800
especially in the wake of World War II.

296
00:17:14,800 --> 00:17:17,600
And then there are the ring mains
of the UK.

297
00:17:17,600 --> 00:17:19,400
Look those up if you've never heard of them.

298
00:17:19,400 --> 00:17:21,120
They’re weird.

299
00:17:21,120 --> 00:17:26,920
And, fun fact, in the UK they actually use split-phase
power on construction sites!

300
00:17:26,920 --> 00:17:31,240
In that case, the potential across the two wires is 110V funnily enough,

301
00:17:31,240 --> 00:17:35,040
with each wire only at 55V potential to ground.

302
00:17:35,040 --> 00:17:38,140
This is done for the express purpose
of increasing safety!

303
00:17:38,140 --> 00:17:41,140
55V is even more safe than 120.

304
00:17:41,140 --> 00:17:44,840
55V is barely above what power
other Ethernet is.

305
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.

306
00:17:51,180 --> 00:17:54,740
So I guess a fair number of UK power tools can be used
over here.

307
00:17:54,740 --> 00:17:56,080
Whaddya know.

308
00:17:56,080 --> 00:18:00,840
Yeah - quick note, for some reason lots of
people will refer to our voltage as 110V

309
00:18:00,840 --> 00:18:02,740
(and thus 110/220)

310
00:18:02,740 --> 00:18:07,280
or maybe 117 or 115 or even
125.

311
00:18:07,280 --> 00:18:10,340
OK, to those of you who do that, just…

312
00:18:10,340 --> 00:18:11,520
it’s 120.

313
00:18:11,520 --> 00:18:15,840
But there is no concrete exact
voltage to any electric grid.

314
00:18:15,840 --> 00:18:21,040
It varies depending on conditions so everything operates within a range of acceptable voltages.

315
00:18:21,040 --> 00:18:26,900
Usually here I get something like 123V but in other
places you might only have 115V.

316
00:18:26,900 --> 00:18:30,720
Or maybe even 110. It’s fine, stop being pedantic
about it.

317
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

318
00:18:34,700 --> 00:18:39,620
electrical system so everyone is clear on
the fact we have 240V power.

319
00:18:39,620 --> 00:18:42,900
It’s a little weird, but it’s there and we do use it.

320
00:18:42,900 --> 00:18:44,900
It’s not like we’re in the dark ages.

321
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!

322
00:18:50,520 --> 00:18:51,140
Ah!

323
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.

324
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

325
00:19:02,400 --> 00:19:04,840
rather than "the standard 240."

326
00:19:04,840 --> 00:19:06,820
That seemed to confuse a lot of people,

327
00:19:06,820 --> 00:19:11,812
especially those of you who until right now didn’t know that we have standard 240!

328
00:19:11,812 --> 00:19:15,580
Apartments often have 208v in their service panels

329
00:19:15,580 --> 00:19:19,620
because many larger buildings are hooked up to a three-phase power supply.

330
00:19:19,620 --> 00:19:22,840
When done in the most common Wye (Y) configuration,

331
00:19:22,840 --> 00:19:30,360
each phase is 120V respective to neutral, but across any two phases you have 208 volts.

332
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.

333
00:19:35,679 --> 00:19:38,420
There will be two hot phases as well
as a neutral.

334
00:19:38,420 --> 00:19:42,600
But, those two hot phases are not from a split-phase transformer,

335
00:19:42,600 --> 00:19:47,720
but are in fact two of three available phases from a three phase transformer.

336
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

337
00:19:54,220 --> 00:19:56,800
208V and not 240V.

338
00:19:56,800 --> 00:19:59,120
It’s actually geometry! In a way.

339
00:19:59,120 --> 00:20:01,000
Or is it trigonometry? Whatever.

340
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.

341
00:20:07,600 --> 00:20:12,929
In fact, they’ll often specifically
have labels on them that say 240V / 208V.

342
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%

343
00:20:19,380 --> 00:20:22,000
of what they would on a 240V circuit.

344
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.

345
00:20:28,380 --> 00:20:31,880
Or, if you have an electric vehicle charging station installed on 208,

346
00:20:31,880 --> 00:20:37,169
it will charge slightly slower than it would on 240.
But, not a big deal.

347
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.

348
00:20:42,860 --> 00:20:47,040
And will stop badgering me about only having 120V.

349
00:20:47,040 --> 00:20:51,340
Just about the only
way we’re held back by our weedy little outlets

350
00:20:51,340 --> 00:20:53,860
is portable things that make heat.

351
00:20:53,860 --> 00:20:56,600
Yes, our kettles and pretty much everything are capped

352
00:20:56,600 --> 00:21:02,700
at 1.5 kilowatts for an 80% safety margin
on a 15A circuit, but really…

353
00:21:02,700 --> 00:21:07,940
aside from space heaters and tea kettles nothing is worse for being capped at 1500 watts.

354
00:21:07,940 --> 00:21:10,500
And when we need more than that we have options.

355
00:21:10,500 --> 00:21:12,380
We always had.

356
00:21:12,380 --> 00:21:16,980
Yes, our electrical system is very very flawed
and our receptacles do just suck.

357
00:21:16,980 --> 00:21:20,780
Really they’re awful. They’re just terribly unsafe.

358
00:21:20,780 --> 00:21:23,920
But; specifically to Brits and Australians -

359
00:21:23,920 --> 00:21:27,520
your obsession with switches on receptacles makes
no sense to me.

360
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.

361
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.

362
00:21:39,380 --> 00:21:41,560
Like - do you just not have that?

363
00:21:41,560 --> 00:21:44,860
Do companies design stuff for you assuming you’ve got that little switch?

364
00:21:44,860 --> 00:21:47,580
Because that’s not my problem.
That’s your problem.

365
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!

366
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

367
00:21:57,380 --> 00:22:00,600
must be "yet another sign of us being wasteful
Americans."

368
00:22:00,600 --> 00:22:01,600
[inhales exasperatedly]

369
00:22:01,600 --> 00:22:06,480
No. There are many many signs of that but this isn’t one of them.

370
00:22:06,480 --> 00:22:09,610
You will never
convince me that your switches on sockets

371
00:22:09,610 --> 00:22:12,420
are anything other than a mild convenience.

372
00:22:12,420 --> 00:22:16,080
And for what it’s worth, we put switches on our power strips

373
00:22:16,080 --> 00:22:21,460
so we have that option for addressing electronics with standby lights and vampire drains.

374
00:22:21,460 --> 00:22:23,140
Oh but what about safety?

375
00:22:23,140 --> 00:22:24,560
My rebuttal?

376
00:22:24,560 --> 00:22:26,200
Just unplug the thing!

377
00:22:26,200 --> 00:22:30,180
You had to reach for the socket anyway to flip that
switch.

378
00:22:30,180 --> 00:22:32,820
It’s not my problem your plugs are so awkward.

379
00:22:32,820 --> 00:22:35,040
And no, sparking is not dangerous.

380
00:22:35,040 --> 00:22:38,220
A spark from inrush current won’t hurt anything.

381
00:22:38,220 --> 00:22:41,780
Really, some of you seem so scared of various
electricity things.

382
00:22:41,780 --> 00:22:42,460
I don’t get it.

383
00:22:42,460 --> 00:22:44,080
I mean, shaver sockets?

384
00:22:44,080 --> 00:22:45,020
Really?

385
00:22:45,020 --> 00:22:47,600
Just put an RCD in the bathroom.

386
00:22:47,600 --> 00:22:51,240
And for being so afraid of that your electric showers are baffling.

387
00:22:51,240 --> 00:22:53,570
Really, I know our electrical system has its flaws

388
00:22:53,570 --> 00:22:57,940
but your perception of how dangerous electricity
is seems really out of whack.

389
00:22:57,940 --> 00:22:59,140
And ring mains?

390
00:22:59,140 --> 00:23:01,240
Really? What year is it?

391
00:23:01,240 --> 00:23:04,700
Now, to be fair your fuses
in the plug; that's pretty cool.

392
00:23:04,700 --> 00:23:05,980
I’ll give you that.

393
00:23:05,980 --> 00:23:08,000
Though they do seem like quite a foot
hazard.

394
00:23:08,000 --> 00:23:09,080
I guess, which is worse?

395
00:23:09,080 --> 00:23:12,760
Shock hazard from 120V or foot hazard from UK plugs? 
[music fades in]

396
00:23:12,760 --> 00:23:14,300
Someone should do a study...

397
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

398
00:23:18,160 --> 00:23:19,260
it’ll be fine…

399
00:23:20,100 --> 00:23:22,680
♫ electrifyingly smooth jazz ♫

400
00:23:23,880 --> 00:23:27,560
That’s what you'll find in most countries
around the world when deal…. Ooh.

401
00:23:28,780 --> 00:23:29,920
[exhales exasperatedly]

402
00:23:30,280 --> 00:23:33,800
To get that full potenti… oh shoot, that’s
not the end of the sentence.

403
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]

404
00:23:38,720 --> 00:23:40,800
To get… mahhhh 
[as he realized he stopped mid-sentence]

405
00:23:40,800 --> 00:23:43,940
And it can still very much kill you, but….

406
00:23:43,940 --> 00:23:46,340
Oh... Yeah, that’s not how the line’s written.

407
00:23:46,340 --> 00:23:49,780
...terminal… this other bit is just to….

408
00:23:49,960 --> 00:23:53,000
[stares befuddledly at the circuit breaker]

409
00:23:53,640 --> 00:23:55,640
Yeah I got that backwards!
I lost…

410
00:23:55,640 --> 00:23:58,520
I lost, I already lost track of which side is which.

411
00:23:58,520 --> 00:24:01,480
Which one is which? Ii is….

412
00:24:01,480 --> 00:24:03,160
This side.

413
00:24:03,160 --> 00:24:06,540
Yes. Our kettles and space heaters…

414
00:24:07,480 --> 00:24:08,340
Oh...

415
00:24:09,400 --> 00:24:13,420
I don't want to see another *laughs in 240V* comment on the internet, OK?

416
00:24:13,420 --> 00:24:15,820
All y'all better have learned now.

417
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.

418
00:24:20,360 --> 00:24:24,920
If that ain't fast enough y'all are wicked impatient.