Hi - ya 48V was the first choice, but looking at dc/dcs it is somewhat 
cheaper to go with parts that have a max voltage somewhere below 48V, 
both in the dc/dc chip and voltage ratings for the various caps that 
will be needed - and can't use electrolytics for other board height 
clearance reasons.  Also I believe that while 24V can be wired with 
impunity, 48V crosses some regulation threshold, at least here in the 
great state of california.  Not sure.  Doesn't matter for the initial 
client at all but designing something that could become large-scale, UL 
& california certifiable architectural lighting without a hitch is a 
nice feature.  tradeoffs...

I wish something like 32 or 34V were a standard.  Enough to be able to 
deliver considerable power without excessive current, but low enough 
voltage to not need anything at all special/different.  Alas.

J



Olin Lathrop wrote:
> Jesse Lackey wrote:
>> I'd like to get 30+ feet per
>> controller, but the board-to-board connector may limit the 24V
>> current to substantially less than that.
>
> So why 24V instead of 48V?  Do you have different regulations perhaps?
> Around here, 48V is about as high as you can go before safety regulations
> start getting in the way.  Between that and the fact that it is/was a common
> telco voltage (possibly for the same max voltage versus saftey tradeoff),
> 48V is a common off the shelf power supply voltage.
>
>
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