Can You Have A Battery Draw If The Positive Is Still Connected

The iii Rules, The Humble Excursion, and Its Place in Our World of Electronics

Greetings new engineers. This is a wonderful place to begin, with the simple circuit, which forms the building block to every slice of electronics in our earth. Once fully understood, you'll be fix to begin your own journey in designing and troubleshooting them yourself.

The Building Blocks of the Circuit

Before diving into a consummate circuit, it'southward wise to beginning wrap your mind around the individual pieces that make up the whole, being catamenia, load, and electrical conductivity. We've organized these principles into three bones rules:

Rule one – Electricity will always want to menstruation from a college voltage to a lower voltage.
Rule 2 – Electricity always has work that needs to exist done.
Rule 3 – Electricity ever needs a path to travel.

Rule i – It'south All About the Flow

Every electronic circuit needs some a power source, whether that'due south from an AA bombardment that yous tin pop into your Xbox One controller or something with a bit more strength like your wall outlet that tin can ability a big number of devices. The electricity that comes flowing out from these sources is measured in voltage, or volts, or but V.

Yeah, we're talking about that kind of voltage! When it's loftier enough information technology can exercise some serious impairment.

Regardless of where this power flows from, its purpose is always the same – to get from one expanse to some other, and in the process to do some work, similar charging your estimator or turning on your lights.

The central component of this flow of power is that electricity volition ever desire to flow from a higher voltage to a lower voltage. Ever. This is called potential . Yous could say that it'south the potential electricity has to move from ane area to another.

Flow of High (Positive) Voltage to Low (Negative) Voltage.

How does this relate to our real earth? Let's take the uncomplicated bombardment as an example:

A battery has ii sides, the negative side is the low voltage, measuring in at 0v, the positive side is the high voltage, measuring in at ane.5v.
Energy will always desire to period out of the positive side of the battery to get to the negative side to find balance.
To do this, it needs to period forth something, usually a copper wire, and practice some work in the process, like turn on a light or spin a motor.

At the cease of the day, all electricity wants to find its equilibrium at ground (0v). The simply way to practice this in a battery is to move from the positive to the negative side. We benefit from this natural desire of energy by placing some objects in the way that it needs to flow through, allowing us to turn on lights, ability motors, and switch transistors on and off in a computer.

This all amounts to Rule 1 – Electricity will always want to flow from a higher voltage to a lower voltage. Remember this; information technology will never modify.

Rule two – Getting Some Work Done

Now, you lot might have some electricity that wants to flow from a higher voltage to a lower voltage, but what's the point? The only reason to make electricity flow is to give it some piece of work to do. This process of electricity doing work in a excursion is chosen load . Without having a load, or some work for electricity to do, and so there is no point in having a circuit. A load tin can exist anything you can imagine, such as:

Spinning a motor which turns the propellers of a drone.
Turning on a LED on a charging cable to indicate that your laptop is plugged in.
Connecting your headset wirelessly with your laptop to listen to music.

Tis' the flavour, electric load comes in many forms, one of which is powering these LEDs. (Image source)

Notice that all of these loads are actions. Electricity e'er makes something concrete happen, fifty-fifty if we can't come across it with our own optics. But why is it chosen a load? You can call back of information technology as a burden to whatever is powering your circuit. Spinning a motor requires electricity, and this takes energy away from your power supply that it once had.

Recall Rule two – Electricity always has work that will need to be washed . Without piece of work, and so a circuit has no utilize.

Rule three – Following a Path

The tertiary and final rule is what makes the first two rules possible – electricity needs a path to travel. This path acts as a kind of middleman. Allow'southward say you plug your laptop charger into a wall socket, and and then into your laptop. It charges, obviously, but without that cord between your figurer and wall outlet, nothing would happen.

This is considering electricity needs a path to follow to get from one destination to another. And the journey is always the same:

Ability – Electricity always starts from a source, like a battery or an outlet.
Journeying – Information technology then takes its journey along a path, doing its work along the way.
Destination – It then arrives at its terminal destination, finding remainder at the everyman voltage signal.

This path that electricity walks on is made upwardly of what's called conductive material, which is made upwardly of common metals like copper, silver, aureate or aluminum. Electricity loves to travel on this stuff. Electricity is also very selective, and information technology won't bother traveling on paths made up of inductive materials. This includes things like rubber, glass and even air.

Come across all of those copper wires? Electricity loves traveling on this conductive textile.

Remember Rule 3 – Electricity always needs a path to travel on . Without a path, it can get nowhere.

Putting Information technology All Together – The Complete Excursion

Let's put all of these rules together at present in a complete definition of a circuit.

A circuit is merely a path that electricity can flow through.

And with that unproblematic concept right there, men and women have gone on to build some insanely circuitous circuits that have sent the human race to space and the depths of our deepest oceans. For now, we'll keep things elementary and put together our first circuit. Here'south what you'll need if you want to follow along:

(ane) nine-volt bombardment
(one) 470 Ω resistor
(i) Generic LED
(3) Test leads with alligator clips

Footstep i – Adding a Power Source

Going back to our Dominion of 3'southward, the first says that electricity will always want to menstruum from a higher voltage to a lower voltage. Okay, so this means we demand some kind of power source in this circuit, we'll add our 9v battery.

The beginning of our circuit starts with a 9v bombardment.

Rule i is now fulfilled. We have some kind of power source that has a high voltage on the positive end (+) and 0v on the negative end (-). Simply all of that electricity is going to waste if we don't exercise something with information technology, and so let'southward give it some piece of work (load).

Stride ii – Calculation Some Piece of work

We at present want our electricity to practise some piece of work for us before it can come up to rest, so let'southward have it plow on a uncomplicated LED light. You've likely seen these everywhere, in your Christmas tree, flashlights, light bulbs, etc… So we'll take this LED and identify it on the other side of our battery.

Now, the one thing to mention about a LED is that it'southward really sensitive and can't have too much power running through information technology, so we need to add together what's called a resistor. We won't get into the details now, just simply know that a resistor volition do similar its name says – resist the flow of electricity enough for our LED to handle it. Let's identify that resistor to the left of our LED.

Adding some work to our excursion with a LED and resistor.

Great, Rule 2 is now complete, and our electricity has some piece of work to do. Just information technology doesn't have a fashion to complete its work without a path, allow'due south add that at present.

Footstep 3 – Providing a Path

This part is simple, nosotros but need to connect our alligator clips between all of the components on our circuit. If yous practice this correctly, then your LED will shine bright! Remember, when connecting wires to a battery, always connect the positive terminate get-go, and then the negative. Check out the motion-picture show below for how information technology all needs to be connected together.

Our electricity now has a path to flow through with the added alligator clips

Types of Circuits

At present, before you go running off into the wild and building your ain circuits, you need to know about two ways to describe a circuit, one of which might ruin your excursion's day, they include:

Airtight or Open up Excursion

A circuit is considered a closed circuit when at that place is a consummate path available for electricity to travel on. This is also referred to as a complete excursion. Now, if your circuit isn't working as intended, then this ways that information technology'due south an open circuit . This can be caused by several things, including a loose connexion or a broken wire.

Here's an piece of cake, visual way to understand the difference between a closed or open circuit, check out the excursion diagram below and find that it'due south the aforementioned excursion nosotros made above, except now it has a switch.

Here's a diagram of the circuit we made above. Notice the add-on of a switch.

Right at present, the switch is upwards, and you'll see that electricity doesn't have a smooth path to flow through since the switch is breaking the connectedness. This is an open circuit. Merely what happens if you flip the switch?

Now our switch is triggered, which completes the excursion, allowing electricity to flow to our LED!

Aha! Now you but created a consummate path for your electricity to travel on, and your LED will plough on! This is a airtight circuit.

Short Circuit

So there's the short circuit . When you don't give your circuit any piece of work to do, merely you still provide some power, fix for some bug. Check out our circuit below, nosotros took out the LED, resistor, and switch, leaving just our copper wire and battery.

Hither's a circuit well on its mode to becoming a short excursion! Without whatsoever work to do this bombardment will shortly fire out.

If we hook this thing together in its physical grade, then the battery and wire are going to go super hot, and somewhen, the battery will run out of juice. Why does this happen? When yous give electricity some work to exercise in a circuit similar lighting an LED or spinning a motor, then this limits how much electricity will flow through your circuit.

But the minute you lot take any of that work out of your excursion, the electricity goes crazy and runs around its path at full speed without anything property it back. If you let this happen for an extended catamenia of fourth dimension, then you'll detect yourself with a damaged power supply, a drained battery, or maybe something even worse, similar a fire!

Whoa! Don't effort this at habitation. Here'due south a hefty 12v lantern battery being brusque-circuited in the name of scientific discipline. (Epitome source)

So if you always work with a circuit and your wire or battery is getting super hot, so turn everything off immediately and look for any brusque circuits.

Y'all Are Now Unsafe

In that location y'all go, young electronics chief, you now have all the information you need to control the humble circuit. By understanding how a excursion works, yous'll presently exist able to tackle projects of all shapes and sizes. But earlier beginning your own journey, recall the Guiding Rule of Threes:

Rule 1 – Electricity volition always desire to catamenia from a higher voltage to a lower voltage.
Rule ii – Electricity ever has work that needs to be done.
Rule 3 – Electricity always needs a path to travel on.

And if your circuit ever gets super hot, shut it downwards! Yous've got a short circuit.

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