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controlling light bulbs in series setup

controlling light bulbs in series setup

controlling light bulbs in series setup

(OP)
hi everyone

was wondering how you can individually control two light bulbs in a series circuit

the scenario would be something like you have a single power source and two bulbs, one red one green, and two switches.

i know there is an easy way to do this using a parallel arrangement but is there a way to design a series setup(i.e. the bulbs are connected in series, switches also in series, in one loop) that would allow you to individually control the two bulbs? ok to include use of other parts like capacitors and diodes important part is that each switch should exclusively control one bulb.

thanks for any help you can provide

RE: controlling light bulbs in series setup

This problem has one simple solution and probably an infinte number of more complex solutions.

The simple one:

A  Use AC. If your bulbs are 110 V, use 220 V.

B  Put a diode across each lamp. One diode pointing from the switches and one diode pointing to the switches.

C  Put two switches in series. Put a diode across each switch. One diode pointing to the lamps and one diode in the opposite direction.

D  Test.

E  Bet someone that it can be done.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: controlling light bulbs in series setup

AC or DC?
Sounds like the kind of trick puzzle people dream up late after having had one too many.
Like the one about finding out which lightbulb belongs to which switch when the switches are downstairs and the bulbs are in the attic......

Yes, it's possible.

Benta.

RE: controlling light bulbs in series setup

Use a current source (rather than voltage source) to run the series-connected lamps, and put the switches in shunt with the lamps.

RE: controlling light bulbs in series setup

That would not put bulbs and switches in series? Would it?

But neat solution. Isn't that how run-way lights in air fields are connected?

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: controlling light bulbs in series setup

Switches in series wasn't stated as a requirement, just as an "ie".  

Can't speak to the airfields, but series-connected lighting with a voltage:current transformer was a common early method of street lighting.  Most of that stuff has been ripped out by now though

RE: controlling light bulbs in series setup

Runway/taxiway lighting in the US is series connected, going through a constant-current regulating transformer to allow the lights to be dimmed.

More info at Crouse-Hinds website if anyone is interested..

RE: controlling light bulbs in series setup

Semantics again. I.e. = id est = that is.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: controlling light bulbs in series setup

peebee, you're probably thinking "e.g.", or exempli gratia, meaning "for example".

Dan - Owner
http://www.Hi-TecDesigns.com

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