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I am trying to build the simplest possible circuit that will drain an AA battery at a known rate. The circuit would include a battery, a switch and a lamp (LED or bulb) and a resistor in parallel to drain the battery in less than 30 minutes. The exact time to drain the battery doesn't matter, since the idea is to build two separate circuits to compare how quickly the LED drains the battery compared with the bulb.

Also, I am trying to figure out how to do this on a bread board.

I'd appreciate any help!

Why not just draw exactly what you have described in CL?

If you draw it as a simulatable circuit you can plot currents voltages and power dissipations around your circuit.

Note however that battery models in CL are inexhaustible. See this thread:

https://www.circuitlab.com/forums/power-electronics/topic/6unrchw7/charging-battery/

:)

Hey signality, thanks for the feedback. I am new to CL, but I will give it a go!

OK. This is what I have.

I am not sure of what the NODE1 means, or if I have it in the right place.

Also I am not sure how to do the simulation, but this looks like it should work!

@RogerJH,

Sorry, I forgot the Welcome to CL bit.

:)

Well done, you're nearly there for your first simulatable circuit,

To get the hang of CL - especially for simulation - you need to read:

https://www.circuitlab.com/docs/

and

https://www.circuitlab.com/docs/faq/

There's a lot of useful stuff in the Blog too but it can be hard to find.

Have a look at the plethora of examples too. Not just the CL ones but everyone elses. Don't afraid to play. You can't break anything and you're not messing with anyones original circuits: you can't save your changes to someone elses circuit, only your own copy of it.

The NODE1 label you have put on is just a user editable name for the wire connecting various bits of the circuit together. You can call it anything you like as long as there are no spaces in it: Battery or Vcc or fishpaste.

Its just a name that helps you remember what the wire does and what it connects.

However it's more than that. If you add another component and you can't be bothered to redraw the whole diagram just to fit the wire extra connecting the Vcc wire to it, you can put a label, Vcc on the end of the new component that you want to wire to Vcc and bingo: the two points are connected.

More about Wires and nodes:

If you hover your mouse over the end of a lead of a component that you have placed on the schematic a large, light grey dot will appear right at the end of the wire.

That is the (only valid) connection point for that component lead. Also referred to as a Node:

https://www.circuitlab.com/docs/the-basics/#nodes

If you Left-click and hold on that grey dot then drag the mouse cursor, a wire will appear.

Drag it to the next node you wish to join.

If you need to turn a corner, let go and then repeat the process on the node dot at the end of the wire you have just drawn and drag at right angles.

Note that you can also join nodes just by attaching a label to a node and then attaching a new label with the same name to another node. Those two nodes are now connected exactly as if you has drawn a wire between them:

https://www.circuitlab.com/docs/the-basics/#named_nodes

You can also draw a wire by clicking on the "Wire" button on the left hand palette then left-click and drag and release on the schematic.

To repeat a placement press shift before you click on the component you wish to place.

However, you must be consistent in your labelling:

https://www.circuitlab.com/forums/support/topic/86m9393x/bug-report-inconsistency-in-using-net-label-as-a-voltage/

Note also that CL assigns arbitrary but sequential node names to unlabelled nodes.

This can lead to very confusing results where node names are used in expressions for arbitrary sources and plot expressions.

Suppose you have a circuit with 17 nodes then you replace a resistor with a piece of wire.

Your circuit now has only 16 nodes. Suppose the node you removed was Node17.

Suppose you then add a new component in a different location that then adds a new node (by inserting a resistor in a wire for example). The new node will be auto-labelled by CL as Node17.

If you now add the first resistor back in it's original location. The node that reappears will now be auto-labelled Node18 and not Node17 as it was originally.

More complex editing makes a more comprehensive mess of the CL assigned node names.

If you put node name labels on all the nodes you are interested in then they won't change numbering or flicker in and out of existence as you edit your circuit. They will then always be valid in your expressions.

You can set up explicit voltage sources for the power supplies in CL or create an implicit supply using a node or net name. For example, the +1V or +1 node label invokes an implicit 1V source: https://www.circuitlab.com/circuit/a5bzf7/good-netname-and-a-free-voltage-source/ However, in: https://www.circuitlab.com/circuit/96br67/bad-net-name/ CL throws an error because the explicit 1V source, V1, is then in parallel with the implied source created by the node label.

Wow! This is awesome help. Thank you, signality, I really appreciate the time you took to respond!