About this video
This short build step shows how to insert AA batteries into a battery holder with the negative end against the spring. The batteries add mass to hold the holder steady and supply the power for testing circuits. The wires are then separated so they do not short out, a dab of hot glue anchors the holder, and two single-pole-double-throw switches are set at about 90 degrees with their inner contacts touching.
You'll be able to
- insert AA batteries into a holder with the correct polarity.
- explain why the wires must be kept apart once power can flow.
- position two SPDT switches for the next step of the build.
Key words
- Polarity
- The orientation of a battery's positive and negative ends, which must match the holder for current to flow the right way.
- Short circuit
- An unintended path with almost no resistance between two wires, which stops the circuit working as intended.
- Single-pole-double-throw (SPDT) switch
- A switch that connects one input to one of two outputs, depending on its position.
- Hot glue
- A quick-setting adhesive used here to fix the holder in place.
Transcript
Okay, so in this video, we’re going to insert the AA batteries into our battery holder. The negative side goes against the spring, and the positive side goes away from it. This is going to allow us to hold our battery holder in place a little better, because it will add some mass to it.
And it will also give us the power we need to test our circuits, and eventually run our bot. So because power can now flow, we do want to separate those wires so they don't short out. And now we're going to put a blob of hot glue down in the corner – the same corner as the red and black wires are close to.
And the blob should be about half the size of a dime. So we’re going to take our single-pole-double-throw switches, and we’re going to set them at about a 90° angle to one another, so that they’re lined up like so. And we want the contacts at the top of those single-pole-double-throw switches to be touching one another – the contacts that are on the inside there.
Now we're ready for the next step.
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