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Philips EcoBoost Halogen Lamps

J

James D. Hooker

Jan 1, 1970
0
I haven't cut open a Philips lamp yet, but if you look at some of the Osram
samples they don't seem to use a traditional tranformer. Seems to be more
like the switching unit you get in a dimmer switch which just chops up the
line voltage to limit lamp power. This sort of circuit is perhaps cheaper
and smaller than using a full electronic tranformer. Perhaps it also
explains why the luminous efficacy of these lamps is quite a bit lower than
the bare 12V capsules.

If we consider first that the 12V 20W IR capsule operates at 24lm/W, factor
in 5% absorption losses due to the second outer glass bulb, and then assume
a 90% efficiency for the "transformer", it indeed brings us down to a total
system efficacy of 20.5lm/W.

James
 
C

Clive Mitchell

Jan 1, 1970
0
James D. said:
I haven't cut open a Philips lamp yet, but if you look at some of the
Osram samples they don't seem to use a traditional tranformer. Seems
to be more like the switching unit you get in a dimmer switch which
just chops up the line voltage to limit lamp power. This sort of
circuit is perhaps cheaper and smaller than using a full electronic
tranformer. Perhaps it also explains why the luminous efficacy of these
lamps is quite a bit lower than the bare 12V capsules.

Are you sure it's not a miniature electronic ballast like the ones in
compact fluorescent lights? The output is directly to the lamp with no
low voltage wiring or connectors involved so an electronic ballast is a
bit simpler than an electronic transformer. If it was a phase angle
control circuit it would require a significant choke to limit RF
emissions.
 
V

Victor Roberts

Jan 1, 1970
0
Are you sure it's not a miniature electronic ballast like the ones in
compact fluorescent lights? The output is directly to the lamp with no
low voltage wiring or connectors involved so an electronic ballast is a
bit simpler than an electronic transformer. If it was a phase angle
control circuit it would require a significant choke to limit RF
emissions.

I think we're all hung up here on jargon. But, first to go
back to James' comment. A line frequency transformer would
be far too big and heavy compared to an electronic power
supply of some type.

Now, on to the jargon. I'm not sure exactly what you mean
by an electronic transformer, but I was not implying that
the circuit would have line-to-load isolation or would
produce a fixed output voltage independent of load.

A number of switching circuit have been developed that could
be used to run a 12-volt filament from a 120-volt or
240-volt power line, and all are simpler than an electronic
ballasts since they don't need to deal with a negative
impedance load, high starting voltage or additional
electrode heating circuits. Some people have proposed a
simple series capacitor, but that is undesirable for two
reasons: 1) poor input power factor; and 2) the fact that a
series capacitor would pass voltage spikes right on to the
filament, causing it to burn out.

--
Vic Roberts
http://www.RobertsResearchInc.com
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S

Simon Waldman

Jan 1, 1970
0
Paul said:
"One of Philips’s revolutionary products in this respect is an energy
saving halogen bulb for the home -- called Edore. It offers clear
crisp lighting and uses 50% less energy than the ordinary household
bulb. Available in the second half of 2007, the Edore is a retrofit
halogen bulb that can be used in a normal fitting."

Source:
http://www.newscenter.philips.com/About/News/press/article-15721.html

In terms of luminous efficacy, is it reasonable to assume these
products will be more or less comparable to GE's forthcoming (first
generation) high efficiency lamp (i.e., ~ 30 lpw)?

I doubt it. If these are the same as the prototype retrofit halogen
lamps that Philips were showing at Light & Build Frankfurt last year,
they are LV halogen capsules fitted with transformer inside a GLS bulb.
I'm not sure whether they use infra-red coatings, but it's certainly
possible.
Unless there is another new technology involved, I would be surprised to
see these lamps achieve a higher efficacy than existing low voltage IR
halogen capsules. If I remember right, existing capsules manage around
26lm/W.

On the other hand, these are available now (or very soon), and GEs
product, even if it manages 30 lm/W, isn't :)
 
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