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In the last video, we talked about series
in parallel and color coding our circuits,
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so that we were able to
see series in parallel.
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Now, let me show you how we actually
do that in a battery charging circuit.
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This is useful if you have a motor home,
okay?
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Here are two batteries, for example.
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Let's decide if they're in series or
parallel.
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Right here, let's color code our circuit.
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So here's one.
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Is that an extraordinary or
an ordinary node?
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That's an ordinary node.
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Here's another ordinary node.
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And finally, one more ordinary.
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Okay, so I have three ordinary nodes.
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I have two batteries that
are connected by one color.
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And so they are in series.
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12 volts is in series
with the other 12 volts.
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So the total voltage that I have is
12 volts in series with 12 volts or
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24 volts from top to bottom.
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Now, I would connect my
batteries up just like this.
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See if I two car batteries, for
example and I wanted to hook them up.
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I would literally take the positive
arm of one battery that would
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come out to the top of my 24 volts.
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I would take the negative terminal of one
battery and connect it to the positive
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terminal of the other, and I'd take
the negative terminal of that battery,
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and connect it up, and
I would end up with a 24-volt battery.
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Now, let's also talk about the current.
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Let's say that this battery is
capable of delivering 20 amp hours.
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Well, I I would now have two batteries.
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Both capable of delivering 20-amp hours,
but they would have 24 volts.
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So they still would be a 24 volt,
20-amp hour battery.
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Now, let's go to the parallel connection.
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Here I have two 12-volt batteries and
let's color-code them, and
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see if they really are in parallel.
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So here is one.
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Is that an ordinary or
an extraordinary node?
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That's an extraordinary node.
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And right here, ordinary or extraordinary.
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That's an extra ordinary node, okay?
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Well, in my parallel connection,
I can see that they are parallel,
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because they share the two colors,
red and yellow.
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And remember that if I
have a parallel circuit,
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the voltage stays the same,
but what does change?
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Okay, so I hook them up this way.
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I will connect both positive terminals
together and that will come out to here,
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and the negative terminals
will come out there.
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What happens is my voltage the same,
but I can get more current.
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So instead of having the 20-amp hour
system, I have a 40-amp hour system.
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So let's go back and take a look.
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Here I have my batteries in series,
I doubled my voltage.
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Here I have my batteries in parallel,
I'm doubling my current.
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Now, here some other combinations.
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Let's see what's in
series in parallel here.
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Okay, there is one ordinary or
extraordinary node.
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Yep, ordinary node.
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Here is ordinary or extraordinary.
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That's extraordinary.
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Here is another extraordinary node and
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I still have one more ordinary
node right there in middle.
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Okay, this is how the batteries would
be hooked up just like in this picture.
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All right, what do I have here?
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I have two batteries right there.
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They're in series, they share one color.
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12 volts in series with 12 volts and
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I have another 12 volts in series
with 12 volts right there.
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And they are in, sorry,
oops, that's not series.
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They are in parallel.
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So I have 12 volts in series
with 12 volts, which is 24 and
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that is parallel with
another 24-volt battery.
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The combination of these gave me both
double voltage and double current.
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Now, let's see another way
we might hook that up.
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Right here,
we could hook up kind of the same thing.
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It sort of looks like it might
be the same, let's check it out.
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Okay, right there,
all of those connect up together.
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How is this different
than my previous case?
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The only thing that's different is
that I am connecting my batteries up
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by putting two in parallel like this and
another two in parallel and
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then connecting those in series.
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So it's like having two parallel
connections in series Instead of two
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series connections in parallel.
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Do I still get the same thing?
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Well, let's see.
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So right here, I had a 12-volt
system that was 20-amp hour and
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another 12-volt system
that was 20-amp hour.
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Sorry, what do I have right here?
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I have a 12-volt system,
but it is 40 amp hour and
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I have another 12-volt system
that is 40 amp hour and
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I put the 2 of those together and
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the 12 volts in series
are going to give me 24 volts.
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Now, let's talk about charging batteries.
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I have a 12-volt battery charger and
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I reconnect up like this in order
to charge my 12-volt battery.
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If I wanted to charge my 24-volt system
with my 12-volt battery chargers,
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what would I do?
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I will connect the first battery charger
here and the second battery charger there.
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If I wanted to pick my system this way,
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I would be connecting at
12-volt charger here.
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Another 12 the bottom part of the 12
volt charger there, here and here.
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So in conclusion, the things that
we talked about today are voltage,
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current and resistance.
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Variable resistors and resistive sensors.
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Measuring voltage currents and resistance.
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Series and parallel elements.
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Node, paths and loops.
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We'll be talking about these
again throughout the semester.
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Did you wonder where the picture
was from the front slide?
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That's from Peekaboo Slot Canyon
near Kanab, Utah.
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Thank you for joining me today.