Hi, my name's Mr. Brown, and welcome to this lesson on connecting components safely.

And we'll be thinking about electrical components.

We'll be thinking about keeping safe with electrical components, and we'll be thinking about adding all of these components together into our data logger cases and doing this safely and effectively.

Okay, so let's get on, and we'll have a look at the learning outcome, the lesson cycle and the keywords before we get on with the lesson.

The learning outcome for today's lesson is to identify safety measures in electrical circuits and instal components safely.

The keywords that we're going to be using today, well, the first keyword is safety measures.

And safety measures are actions taken to prevent accidents when working with electricity.

Electrical insulator's the next keyword, and that's something that stops electricity passing through it, and electrical conductor, that's something that allows electricity to pass through it.

So those two are opposite each other.

The lesson outlined today, two learning cycles.

The first one, we'll be learning about safe electrical circuits, and then we'll be applying safety measures in electrical circuits.

We start with lesson cycle one, and we'll be learning and thinking about safe electrical circuits and how we keep safe when we're using electrical circuits.

So, an electrical circuit for a data logger contains the following components.

Some simple, easy components.

We've got a battery pack, and this has got zinc-carbon cells in it.

We've got a micro:bit and the components work together so that electricity flows through and the micro:bit works.

And very, very simply using that black and red wire that connects the battery pack into the micro:bit.

That's what gives it the power, connects the simple circuit.

Now, I mentioned that there were zinc-carbon cells being used in this battery pack, and that's because there are different sizes and different types of cells and batteries.

So we're gonna talk about the differences now.

So this circuit uses two AAA cells.

Now, those two AAA cells are in the battery pack safely installed there.

Now they're zinc-carbon cells, rather than alkaline or rechargeable cells.

And we're going to talk about the difference between those.

So when we are thinking about safety measures, what we're thinking about with regards to the type of batteries are that actually if we use zinc-carbon cells, they're used because they're less likely to short circuit or to get too hot.

That doesn't mean that there won't be a short circuit, it doesn't mean that they won't get hot, but they are less likely.

So they're a bit safer to use in the classroom.

Another safety measure that we can use that if the cells do look damaged, you must tell the teacher and you mustn't touch them.

We always make sure that we keep water away from circuits and cells and we always follow teacher instructions carefully.

Check for understanding here.

As a safety measure, which type of cell is best to use in school to make a simple circuit? Is it A, rechargeable batteries, B, zinc-carbon batteries, or C, alkaline batteries? Which one do you think is correct? A, B, or C? That's correct, zinc-carbon cells are the best ones to use in school to make a simple circuit and that's purely because they are less likely to get hot and they're less likely to short circuit.

Doesn't mean they won't, but it does mean that they are less likely than rechargeable and alkaline batteries.

Now rechargeable and alkaline batteries, if we are pretty careful with them, they can be used.

However, zinc-carbon cells are slightly more safe.

Okay, talking about electrical insulators and conductors now.

Electrical insulators stop electricity passing through them and electrical conductors allow electricity to pass through them.

Now here we've got a table and we have, on the left hand side, we've got electrical insulating materials and that includes plastic, wood, glass and paper.

And on the right hand side, we've got electrical conducting materials.

Those are the ones that let electricity come through them and that's copper, aluminium, steel and bronze.

Now in some wires with electrical conductors, most wires need an electrical conductor to allow the electricity to flow through them.

And quite often we use a material like copper, and there on the diagram there you can see the copper wire sticking out.

Now this is what makes the electrical components work.

So it allows electricity to flow from one end of the copper wire to the other.

Now just as equally as important are electrical insulators in wires.

Now most wires, so most copper wires are covered in an electrical insulator, some sort of plastic.

And this is to help us as a safety measure to protect us from the electricity which flows through the copper wire.

Now going back to the diagram that we looked at on the previous slide, we've got the copper wire that you can see sticking out either side, but we're now talking about the plastic covering there, that's the electrical insulator and that's the bit that protects us from electricity flowing through the copper wires.

It's really dangerous to actually touch the wires when we've got electricity going through them and that's why we have plastic covering over them to protect us.

And all of this, these safety measures that we've actually got in place, these help us from getting an electric shock.

Check for understanding.

Let's have a look at this diagram again that we've looked at before.

So which part of the image shows an electrical insulator? Is it A, B, or C? Which part is an electrical insulator? Right, make a choice, think about which one you think is correct.

That's correct, well done.

It's B, the outer covering is an electrical insulator and that's made of plastic which stops electricity from flowing through it and it stops us from getting electric shocks or having issues when we've got bare wire with electricity going through it.

Onto task A and now a chance for you to do some work.

So the first task is we'd like you to discuss how to keep safe when using a micro:bit in an electrical circuit.

Now, we're very fortunate that micro:bits and the battery packs, they're fairly well insulated, they're fairly secure, the circuit is quite complete already.

However, there's still things that we might want to do to make sure that we are keeping safe when we are using a micro:bit.

So I'd like you to first of all spend five minutes or so just talking about how you are going to keep safe when using a micro:bit in an electrical circuit.

Okay, do that, and then we'll move on to the second part of the task.

Right, the second part of the task is we've got a table here and you might have remembered doing that table earlier on in this learning cycle and there's a table here which has materials which you can sort into electrical insulators and electrical conductors.

So can you think of four electrical insulating materials and then on the right hand side, four electrical conducting materials.

So you've got insulating materials on the left and conducting materials on the right.

Now there is a worksheet.

You'll be able to use this table from the worksheet or if you just want to write it down in two columns, that's entirely up to you.

It's not a problem whatsoever.

But what we want to do is now we've got a whole list of how to keep safe when using a micro:bit.

This might actually help you 'cause we're gonna start thinking about materials.

So can you complete the table and sort the materials into insulators and conductors? Right, off you go, think about the different materials you're going to do and I'm sure you can discuss it as a group, as a class, or just with individuals and we'll let you get on with this task.

Good.

Off you go.

Okay, so Izzy and her group talked about safety measures.

Remember, this is part one when using a micro:bit in an electrical circuit.

So she said if something doesn't look right, we are gonna tell the teacher and we're not gonna touch anything.

Really good advice.

They're gonna make sure that the battery pack is connected securely to the micro:bit.

They're going to check if the wires are broken, 'cause if the wires are broken, remember that insulator is gonna be broken and the bare wire will be there, and they're gonna make sure that no water is anywhere near.

And I think that's really good advice.

Izzy and her group then went on and completed the table by adding examples of materials that are insulators and conductors of electricity.

And on the left she has put plastic, wood, glass and paper.

And on the right hand side, she's got copper, aluminium, steel and bronze.

Right, I'm sure you've been able to come up with, you may well have come up with different ideas to these materials.

I'm sure there's lots of flexibility, but there's lots of other answers that could have been there and I'm sure you've thought of some really safe ways of being careful around electrical circuits.

Okay, we are now ready to move on to learning cycle two.

Now, learning cycle two is applying those safety measures that we've thought about and implementing them and applying them into electrical circuits that we are going to use ourselves.

So we're gonna consider our safety measures that we talked about in learning cycle one when we are using micro:bits and battery packs.

So think about the things that you talked about when we're using electrical circuits.

Now, battery packs or a micro:bit do not have exposed wires.

That's a really good thing when they're closed, we need to make sure that they are closed and they attach to the micro:bit securely.

You can see where that arrow is pointing there, that there's a slot for the battery packs to connect, and they connect really easily.

They really do.

Might need to push them in quite tightly but if you are gonna try to remove them, it's really tricky.

And I have to say, even I've made this mistake, that there's been some times when I've tried to take them out and I've pulled them and actually the wires have come out, not that wire connector.

So they are really tricky.

So if you're having trouble with that and you do need to disconnect them, then do speak, do get some advice, 'cause they are quite tricky to remove once you put them in.

And of course, we need to think about all of those safety advices, those safety measures that we've thought of in learning cycle one where we're working with any electrical circuits.

This one is a nice simple safe circuit but things still can go wrong if we are not thinking about the safety measures we need to use.

Right, Jacob has noticed that his micro:bit doesn't actually work, even though the battery pack is in the data logger case, and he's not quite sure why it isn't working.

So the battery pack isn't hot, the components are in the data logger case but it's still not working and he's not quite sure why.

So what safety measures does Jacob need? Have a think, just pause for a moment.

What safety measures does Jacob need just to check that everything's okay and to make sure it's all nice and safe? Have a think and we'll come back in a couple of seconds and talk about it.

Okay, something might need, could be very, very simple, but he needs to check that the battery pack is connected properly.

If it does become hot, thankfully it isn't.

Or the cells need checking, he might not, he should not remove the battery pack or the cover, and he might want to ask an adult for some help because something might have gone wrong with the cells inside the battery pack and so therefore it might be worth him just checking with an adult about what the problem might be.

Here's a check for understanding.

Why should the battery pack cover stay in place? Is it A, the electrical components will be unprotected, B, the electrical components will not work, or C, the electrical components only work with a cover in place.

So why should the battery pack cover stay in place? That's right, it's A.

A, unprotected electrical components can be dangerous.

Now, this is why the battery pack cover should stay in place and he might want to seek someone else, or well this is Jacob's example from the previous slide.

He might need to seek for some advice.

If we have the battery pack cover taken off, the electrical components will be unprotected.

However, the electrical components will still work, 'cause the connection is still made and the components will work with the cover on or with the cover off.

Now, electrical tape can also be used as a safety measure.

Now, can also be known as an insulating tape and that's an insulator.

So that stopped electricity passing through.

If you think back to learning cycle one when we were talking about insulators and conductors, this insulating electrical tape is an electrical insulator so it doesn't let electricity pass through it.

And this is made from polyvinyl chloride or PVC, you might have heard of that term before.

An electrical tape can be used to cover wires that might be exposed or secure them in place securely.

Okay, check for understanding.

We've just spoken about this so can you remember, electrical tape is usually made from fabric, A, fabric such as cotton, B, wood, such as MDF, or C, plastic, such as PVC.

Which do you think it is? A, fabric, B, wood, or C, plastic.

Off you go.

What do you think? That's right.

Well done.

It's C, it's plastic, such as PVC is often what electrical tape is made from.

Now Jacob, he's noticed something else might be a bit of a problem and the wires for his micro:bit keep coming loose and sticking out of his data logger case.

So what measures does Jacob need to keep his wires secure but also safe? So everything's connected correctly but every time he closes the lid, the wires come loose and start sticking out and going places that he doesn't really want them to do.

So he wants them to keep them safe but he also wants to keep them secure.

What could he do? Have a think and discuss what you think he could do.

Okay, so one idea is that he could use a small piece of electrical tape to actually keep the wires in place.

He still needs to make sure that the wires are carefully and safely attached to the micro:bit.

But if it's just a matter of the wires moving about a bit and he wants to actually stick them into place, electrical tape or electrical insulating tape is a really good thing to use.

Now, Jacob is still having problems with the micro:bit and the wires are being checked and the cells are being checked, he's checked everything and he still doesn't know what the problem is.

So he's checked the batteries, they're all sorted, the battery pack and the cells inside, they're all fine.

He's got the wires all connected, they're not moving now.

What safety measures does he need now? What do you think the problem might be? Right, he might need to just double check that his coding's correct.

So he might need to carefully attach the data cable to a computer and check that the correct micro:bit hex file has been downloaded.

Remember, micro:bits can only hold one hex file at a time.

So if he's downloaded the wrong one, it might not work.

Or if there's a problem with the coding, he might need to change that as well.

Okay, task B, now we're getting to the stage where our data logger cases aren't gonna be fully completed.

So you've got a completed data logger case, you might have a micro:bit and a battery pack with cells in it.

And today is all about putting all of this together.

Now, we need to make sure that when we're doing this, we are thinking about safety measures.

So I've got a checklist there for you just to go through.

So first of all, check that the correct micro:bit hex file has been downloaded.

It's best to do that before you start putting the micro:bit into the data logger case.

You can still do it when it's already installed, but it's a good idea just to test it, just to check that it still works.

You then need to connect the micro:bit and the battery pack safely.

You then need to secure the micro:bit and the battery pack into the case safely.

You then need to make sure that the data cable can be accessed.

Let's say you do want to change something with the hex file and with the code, then you'll be able to connect it straight to the computer.

You then might want to use, and this is a might, you might want to use electrical tape to keep wires in place.

And finally the best thing, let's check that the micro:bit data logger case actually works.

So you've got a checklist there, you know what to do.

This is the finishing touches, we're putting everything together.

So we've got a finished data logger case, we've got finished code, we've got finished micro:bit.

It's now just putting them all together and making sure we're safe when we're doing so.

Right, I'm gonna let you get on, I look forward to seeing these finalised designs and we want to see that the micro:bit works.

Okay, well done in advance and I look forward to seeing what you've been doing.

Off you go.

Right, welcome back.

I'm sure you've got to the stage now when everything is completed and your whole project design is ready.

So let's go back to Jacob and see how he's got on.

So he thought about the safety measures he would need and he made sure that his electrical components were safe to use.

He then went through the checklist.

So he checked that the correct micro:bit file had been downloaded.

He connected the micro:bit and the battery pack correctly.

He secured them into the case safely.

He made sure that there was access to the data cable and he used electrical tape to keep some wires in place and he checked that the micro:bit worked, and it did.

So well done Jacob, and well done to you as well.

I'm sure you've all got to the stage where Jacob has, so well done.

You've worked really, really hard on this, and we've now got a finalise finished product.

Congratulations.

Let's go through finally the summary of the key learning points from today.

So the first key learning is that an electrical insulator stops electricity passing through it.

Second, an electrical conductor allows electricity to pass through it.

Thirdly, safety measures are essential when working with electricity.

And lastly, all electrical components need to be placed into the data logger case safely and securely.

And I'm sure you've got to that stage now.

You've done a fabulous job.

Thank you ever so much for being with me today.

I'm sure you're really proud of the work that you've completed.

And we are now ready to start testing them, so well done.

Congratulations, and I will see you and work with you next time.

Well done everybody.

See you next time.