Circuits difficult to solve with switches

[Picuino]

I want to find circuits that are difficult to solve (but not too much), with switches, similar to mazes with creative commons license or public domain.
The goal is to be able to teach beginners to understand electrical circuits, so they shouldn't be too complicated, but they shouldn't be easily solved by trial and error either.

Does anyone know where I can find more similar circuits with free license so I can publish them in my web?

Attached is an example circuit.

[Picuino]

Another example circuit.

[jpanhalt]

Try logic gates, like an XOR.

[Picuino]

Thanks, but it is to teach how to think about the operation of electrical circuits to beginners who do not yet know about logic gates. They only know how switches, battery switches, light bulbs, etc. work.

[jpanhalt]

You don't have to call them "logic gates."  Just give the students the truth table (don't call it that) and ask that they duplicate.  On a personal note, my current home was wired by professional electricians.  Not a single 3-way light switch works properly.  Hence, XOR logic by any other name was foreign to those electricians.

[Picuino]

The problem with the XOR function is that it has two "True" positions that turn on the light. I intend for the circuit to only have one switch position that turns on the light, to make it a little more difficult.

Attached is a drawing of the XOR function with switches.

[Picuino]

On a personal note, my current home was wired by professional electricians.  Not a single 3-way light switch works properly.  Hence, XOR logic by any other name was foreign to those electricians.

I hope my students will leave the course with better knowledge ;-)

[james_s]

You don't have to call them "logic gates."  Just give the students the truth table (don't call it that) and ask that they duplicate.  On a personal note, my current home was wired by professional electricians.  Not a single 3-way light switch works properly.  Hence, XOR logic by any other name was foreign to those electricians.

I have cleaned up multiple jobs done by "professional" electricians and HVAC techs lately, I don't even know how they manage to screw some stuff up so badly.

[jpanhalt]

I have cleaned up multiple jobs done by "professional" electricians and HVAC techs lately, I don't even know how they manage to screw some stuff up so badly.

They are very ingenious, so the saying goes.

[themadhippy]

why do you americans call it  a 3 way switch? theirs only 2 ways , if its due to switching from 3 locations, wrong again ,your using 2way and intermediate switching

[klr5205]

To steal something I've read before:

"The easiest way is to just accept it.  The other way takes 300 posts" 

[jpanhalt]

why do you americans call it  a 3 way switch? theirs only 2 ways , if its due to switching from 3 locations, wrong again ,your using 2way and intermediate switching

1) Because a normal switch is 2 way -- on or off
2) There are three scenarios relative to the levers: up/up, up/down, and down/down
(Actually one hallway has 3 such switches which should be wired XOR, but aren't.  I'll give the C-student contractor a pass on that.  But incorrectly wiring just 2 switches is unforgivable.)
3) Just to bother you Brits, which we have been doing for almost 250 years.

I'll wait for 298 more responses before replying again.

[RoGeorge]

All I can tell you for sure is that it is not fake, and it's not video editing either.

Solve this 3 switches problem:


 

[TimFox]

why do you americans call it  a 3 way switch? theirs only 2 ways , if its due to switching from 3 locations, wrong again ,your using 2way and intermediate switching

1) Because a normal switch is 2 way -- on or off
2) There are three scenarios relative to the levers: up/up, up/down, and down/down
(Actually one hallway has 3 such switches which should be wired XOR, but aren't.  I'll give the C-student contractor a pass on that.  But incorrectly wiring just 2 switches is unforgivable.)
3) Just to bother you Brits, which we have been doing for almost 250 years.

I'll wait for 298 more responses before replying again.

If you need three switches to control one light, then you add a 4-way switch to the two wires between the two 3-way switches.
Just as 3-way switches are SPDT, the 4-way is DPDT hooked up as a "reversing" switch.
I learned this in junior-high-school electricity class, ca. 1962.

One way not to do two 3-ways is what I found in an older house belonging to my in-laws when they asked me to fix the dining-room light switches. 
Someone had put one SPDT/3-way switch on one wall (above an outlet), and the other on another wall (above another outlet).
Each switch's contacts went to Line and Neutral at the outlet below, and the moving contacts connected to each other through the ceiling light on a single wire.
Unfortunately, at least one switch was make-before-break, so it kept blowing fuses.

[james_s]

why do you americans call it  a 3 way switch? theirs only 2 ways , if its due to switching from 3 locations, wrong again ,your using 2way and intermediate switching

I assumed it's because there are 3 terminals on the switch, likelwise a "4 way" switch that is sometimes installed in the middle between a pair of 3-ways witches has four terminals on it. I've never heard of any switch described as "2 way".

[themadhippy]

I've never heard of any switch described as "2 way".

T'is wot us brits call it,most sparks here would look at you blankly if you said single pole double throw

likelwise a "4 way" switch

Ya mean an Intermediate switch

[james_s]

I've never heard of any switch described as "2 way".

T'is wot us brits call it,most sparks here would look at you blankly if you said single pole double throw

likelwise a "4 way" switch

Ya mean an Intermediate switch

Well, yeah, like many other things they have different names in different parts of the world. We may both speak "English" but it's not quite the same language. There are even regional differences within the same country, here you might sit on a couch or a sofa, my grandmother was from Illinois and called it a davenport. There's all sorts of stuff with names the origin of which has been long forgotten, and many colloquialisms. With any of them you learn what the locals call it and you call it that and people know what you're talking about.