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Spehro Pefhany Spehro Pefhany is offline
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Default CFL ballast design, and using dead lamps for repair

On Thu, 24 Jan 2013 03:46:48 +1000, "David Eather"
wrote:


Nope. I lost three Philips to one power surge and on pulling them apart I
can confirm they use the same caps or worse - mine were marked as 350V DC.
Considering the mains was 240v AC thats not a lot of a safety margin. I
now use whatever is cheapest seeing as it makes no difference to the
quality.


Parts that are marked the same are not necessarily the same. The $1.00
bulbs may contain gold-colored caps marked as 630VDC/125°C.

http://www.discovercircuits.com/dc-m...Capacitor1.jpg

Not sure if the 240V input makes much difference.. they are likely
using a doubler circuit in our (120V) lamps.

I have heard enough stories of people who bought the cheap ones and
had initial failures, exciting failures, and such like to avoid the
low end stuff.

It would be nice if LED lamps got anywhere close to the brightness of
CFL, halogen or incandescent bulbs at a reasonable price, but they are
not very close yet. Maybe in a few years. I bought a couple MR11
"brightest on the market" bulbs to unload the halogen xfmr and allow
me to put a bigger halogen in the centre bulb of a 3-light string, and
they're not even comparable. I'll have to take some quantitative
measurements at some point.