Adam said:
easier to find by full title of "Fremont Street Experience" somehwat
amazinly 2 million incandescent lamps changing to 12.5 million
LEDs,got a public art application for the old lamps?
Two million 12V 5W lamps = 10MVA Youch! I wonder if they had a full
capacity rating or if there was a modest diversity factor that allowed
for only a certain number of lamps being on at any given time.
I used to service Glasgow's only full colour tungsten RGBW display panel
and it didn't like a constant full white load. The only time It had
that for a while was when the software that uploaded the Evening Times
headlines crashed while displaying the full white with red text Logo
causing the panels to cut in and out on their thermal trips until it was
reset.
Given that the Freemont ceilings lamps were just a mere 3/8" diameter,
I'm guessing that they were in the same reflectors as the system I
serviced. Taking a look at my backup panel, the individual colour
reflectors are only about an inch square, so guessing that the new "LED
modules" were just three LEDs, that gives roughly 18 LEDs per square
inch minimum (three per module).
Assuming all LEDs operating at 20mA max at 5V for LED and resistor, that
means a rough power consumption of 3.75MVA When at full white. This
suggests the power saving will help offset the cost of the conversion,
with the added benefit of higher colour purity from the LEDs and a much
lower maintenance overhead.
Damn! You've got to admire the Yanks for their guts to do things "big".
I guess from the description of the arts projects based on the original
lamps that they were using a standard clear lamp with a silicon colour
cover. The sign I serviced was based on clear lamps in reflectors with
coloured strips of plastic in front of them. When there was a storm or
a bird flew into the sign a strip would occasionally fall out, leaving a
patch of white on the display.