About this video
The lecturer builds a power connector for an Arduino. The centre pin is positive and the outer shell is negative. He solders a red and a black wire to the connector, separates the joints with electrical tape, insulates them with shrink tubing, and fits the plastic collar. Testing shows a red LED lighting, and he checks that the Arduino's green LED is on.
You'll be able to
- identify the positive and negative pins on a barrel-style connector.
- explain why tape and shrink tubing prevent shorts.
- check a power connection by looking for indicator LEDs.
Key words
- Barrel connector
- A round power plug with a centre pin and an outer shell.
- Polarity
- The direction of a supply, positive or negative, that must be matched.
- Shrink tubing
- Heat-shrink sleeve that insulates a joint.
- Electrical tape
- Insulating tape used to keep two conductors apart.
- Indicator LED
- A small light that shows a circuit has power or is running.
Transcript
OK. In this video, we're going to show you how to make a power connector for your Arduino. So the most important thing to remember here is that the center pin of our connector is positive. So we're going to connect our red wire to the center pin, and we're just going to loop it around in a loop and hook it through the hole in the center pin.
Once we've done that, we'll crimp the wire to make sure it's firmly in place. And then we're going to solder the wire so that it stays where we put it. We're just using our alligator clip on the helping hands there to hold it in place. We're going to do the same thing for the negative wire, which goes to the outside.
Loop it through, and then we're just going to crimp that in place. Make sure that we've got a pretty good connection between the wire and the metal, and then we're going to, again, solder that wire in place. And once we've got those two wires soldered in place, we need to put something between them, otherwise they'll short out next to each other.
So we're going to just put a piece of electrical tape between those two connections, between the two wires there. And that'll keep them from touching each other and shorting out. Now we're going to take a piece of shrink wrap tubing and slide it up the wires and to the connector.
And this will just help provide a nice snug fit against our final piece. So the shrink wrap tubing is in place. Remember you want to make sure that that shrink wrap tubing is a pretty snug fit. So we're just heating it with our shrink wrap gun and it's all shrunk down now.
And now we're going to insert the plastic fitting, the collar, over the shrink wrap tubing and just twist it into place there on our connector. So now we almost have a completely finished connector. So we're going to take the bottom of the wires and insert them into our five-volt power strip that we have.
So the positive wire goes on the positive side, the negative to the negative side, and then we're just going to loop the wires around and connect to our connector, to our Arduino. And just push it into place. And now we're going to test to see if it works. So we'll turn it on.
And when we turn it on, you can see a bright red LED light up. And we're looking for green LED on the Arduino, and you can see that right in the corner there. So we're ready to go.
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