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Enhanced Snow Village(R) lighting

Light up model buildings easily without big bulky 110V wiring
  [vote for,

Snow Village brand model buildings are illuminated with clip-in 110-volt light sockets with what I'd guess are 7.5 watt bulbs inside. These lights are run direct off 110-volt AC. Although there are optional kits with 6 or 20 lights running off one wire, the wire connecting the lights is big and bulky, and the strings are only useful when the right number of buildings happen to be located suitably.

What I would like to see would be for somebody to manufacture 24-volt light fixtures which mount in place of the 120-volt ones, and which have on the back a small 2-pin male connector and a 2-pin female connector. Along with these would be cable assemblies of various lengths with a female connector at one end and a male plug which could either be used as a "straight" plug or a right-angle plug with straight socket combo (the latter being like the old-style Christmas-tree-light plugs, but smaller).

To power all of these, one would use a current-limitted 24V 7.5A supply. Such a supply could power 24 light bulbs at 7.5 watts each while using smaller wire than is required for the 120-volt units. In the event that someone plugged more than 24 lights into the controller, it would safely limit the current to 7.5 amps, making the lights less bright but assuring that the thinner wires did not overheat. For setups which need more than 7.5 amps, power packs might be sold with multiple independently-current-limitted outputs (though I don't know what the exact UL restrictions on that would be).

supercat, Dec 08 2002


       I think the thickness of the wire actually goes up for lower voltages, if you're drawing the same power.
egnor, Dec 08 2002

       [egnor]: The required conductor thickness goes up with current, but the insulation thickness goes down with voltage. In many 120VAC cables (including those supplied with the Snow Village lights), the insulation thickness dominates. Going to 24 volts at "inherently safe" current levels means that the insulation failure is no longer considered a "dangerous" event as it would be at higher voltages or currents. While the insulation has to be thick and durable enough to work, it does not need to have the engineering margins required for 120VAC operation. Thus, the wire would look more like a typical "wall-brick" cable than like a typical "small appliance cable" [on the latter, you should note that no matter how little current an appliance draws the cable still has a certain 'beefiness' to it].   

       More significantly, the UL rules regarding connectors for "raw" 120VAC are much more stringent than those for current-limitted 24 volt devices. Since a key aspect of the idea is the ability to use connectors to easily daisy-chain or branch-wire the lights, the ability to have smaller connectors would be a very big plus.
supercat, Dec 08 2002

       [moved to Product: Light Bulb; I would have moved it to a model-building category except I can't find such. A searchable category listing might be nice...]
supercat, Dec 09 2002

       Given that a lot of chargers these days have no physical (well, metal) connection to the rechargeable gadget, perhaps you power the whole thing by induction? (No wires at all.)
dalek, Dec 09 2002

       Most inductive power-transfer methods require one device to nestle "inside" the other; such a thing is not really suitable here. The big things I'd like to see improved would be (1) use less-bulky cabling, as would be permitted with "inherently safe" voltages and currents; (2) use more convenient connectors. I don't see inductive "connectors" as being an improvement here.
supercat, Dec 09 2002


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