Fun with electricity

[FireTiger]

OK, so my son had a little Christmas light up snowman-

and the frame ferrous iron (allows magnets to attach)

 

The wiring is 50 incandescent Christmas lights on three strand polarized 110v plug...

​And he had some of those 'magic rocks' (hematite or more likely hematine) ...

 

And when I went in to check on it all of the light bulbs had blown black and the fuse in the plug was still 'good' (not tripped) and the house wiring did not trip.

On the wire before the first lights (between the wall outlet and the first lights) on the frame were these cussed magnets...

 

No burn holes in the wiring casing, no melting as I expected and the wires are still testing good...

Now every light bulb must be replaced with an exact equivalent bulb - but how did this happen.

 

A standard short at that point even on three wire should have closed the circuit before light bulbs then tripped the fuse- this is not what happened.

 

Suggestions?

[Thor.]

Instead of something destructive like a EMP, maybe you should try to see if this is for real or not by replicating it yourself, i wouldn't mind seeing the outcome if you're interested.

 

http://www.youtube.com/watch?v=FLek_3Hpwus

 

Allot of people are saying its fake, but maybe you could prove them wrong

magnets :biggrin:

 

Edited March 4, 2013 by Thor.

[Werne]

@FireTiger It's not a short circuit and magnets got nothing to do with that either.

 

Christmas lights got lamps that are hooked up in series to drop voltage down, in your case it's 110/50=2.2V per bulb. The downside of that type of connection is that if one of those bulbs dies, no bulb works. If you replace the faulty one they all light up. That's why your fuse didn't react.

 

You can use a multimeter or an AA battery and check them individually to see which one died.

[bben46]

My first guess is that as these strings are series wired - as Werne said - only one lamp is actually burned out. But that one interrupted the series circuit. Just looking at it the fuse may not show as open - to really check it you need something like a multimeter or continuity checker. The lamps can also be checked using these instruments or a 1.5v battery. (a 9 volt battery will probably be too much voltage and blow the lamp ) A single lamp pulled just a little loose or not making a good conection in it's socket will also cause the entire string to go dead.

 

Some of these strings have a more expensive socket that allows the current to flow even if a single lamp is out - the big drawback to that is then instead of each lamp getting 1/50th of the voltage ( 2.2 to 2.5 volts) they will get a bit more - one lamp out = 2.25 to 2.55v, 2 lamps out = 2.3 to 2.57 v - the more lamps that are out, the higher the voltage on each of the rest - then at some point you get a chain reaction - the higher voltage kills another lamp, the voltage goes up a bit, another lamp fails, it goes up a bit more, more lamps fail until the voltage is high enough to wipe the rest out in one last flash.

 

A lamp for a 50 light string is rated at about 2.3v, while one for a 25 light string will be rated for 4.8v, and one for a 100 lamp string at just 1.2 v - so, using the wrong lamps can cause them to fail.

 

The fuse only blows when something draws too much current - likely it is a low current fuse and will blow (open) long before the house circuit breaker trips.

 

You may also have a wire broken inside one of the connectors or even in one of the lamp sockets - those Christmas light strings are very cheaply made and can break easily. Just a jerk on the wire can cause the cheap small gauge wire to pull apart inside of the insulation where it can't be seen.

[Thor.]

All Christmas lights are like that, but i wonder if led's are like that sense they can be programmed to go with music.

[Vagrant0]

All Christmas lights are like that, but i wonder if led's are like that sense they can be programmed to go with music.

You can program any kind of light to go with music. All you need is some way to modulate the current. Not likely that each LED has its own programming. At most, with higher end types, you might have a more definite control of what individual lights are triggered when. But most of those lights that light up in sequence like runway lights are usually just hard wired to have multiple lines which are alternated, with all of it being controlled by simple circuitry.

 

I don't think I've seen magnets, even strong magnets, do anything to electric current though. Electric current, by its nature has its own magnetic field which usually prevents any sort of cross-interaction. If anything, it caused the wire to break since you had one charge repelling another without anywhere else to go.

[Werne]

 

All Christmas lights are like that, but i wonder if led's are like that sense they can be programmed to go with music.

You can program any kind of light to go with music. All you need is some way to modulate the current. Not likely that each LED has its own programming. At most, with higher end types, you might have a more definite control of what individual lights are triggered when. But most of those lights that light up in sequence like runway lights are usually just hard wired to have multiple lines which are alternated, with all of it being controlled by simple circuitry.

To provide more info on that:

 

LEDs light up to music in a very simple way, the higher the dB on the oudio output, the higher the wattage sent towards the speakers (to which you connect the LEDs). LEDs start lighting up at cca 1.8V (blue) to 2.0V (white) and a 5mm LED needs aproxmately 20mA. Most low-power amps won't light them up at all.

 

If you use a simple transistor amplifier with a DC adaptor to power the LEDs at 3.5V on max and connect the audio input to the base (maybe even put a resistor, depending on the impulse voltage), you can get the LEDs to blink nicely to the music. Transistor acts as a power amplifier and the output power depends on the base's input voltage and adaptor's power.

 

With additional components you can get different LEDs to blink to different sound frequencies but that's something more complicated. And RGB LEDs are freakin' awesome when you play around with them, you can make it light green until 33% output power, orange till 66% and red from 66-100% but that's even more complicated.

 

With no amplifier, strength of the LED light depends on voltage/current output from the speaker amp alone, it usually either doesn't work at all or burn out your LEDs.

 

Also, the lights that light up in sequences mostly do it through MOSFET electronic switches and CMOS microcontrollers, sometimes even 555 timers, easy but handy circuits for those that want to make them.

[Thor.]

check this out, iff you think thats a woow factor of ten.

 

LED's can do anything

 

Edited March 4, 2013 by Thor.

[Werne]

LED's can do anything

LED is the same thing as that lighbulb in your fridge, the only difference is that lightbulbs heat up the tungsten wire until it glows and LEDs are electroluminescent.

 

You are confusing LEDs with electronic circuits.

[Thor.]

Okay, i still think they are better :teehee: which is cooler