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GE Halogen "modified spectrum" A19s

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merc:
Not in all cases though.

Osram Classic Superstar (halogen GLS retrofit) has "Number of switching cycles" = 50,000 and the balloon tip says: "At 1 min on / 3 min. off".
This is definitely better than most of CFLs.

The linear halogen Sylvania 240 V / 400 W in question has "No. of switching cycles before premature failure (min)" > 8,000 and they don't say anything about the switching scheme.

Medved:
The switching scheme is in the standard and the mandatory rating information (after 2009 in the EU for all lamps for general lighting) is based on that standard. The official statement is "to have unified, but simple rating system for all lamps", how that "works" you know, I guess...

I know the "1min ON/3min OFF" makes way more sense for PIR sensor applications, but the EU regulations just ordered the 15min of ON time.

Or better to sat: All that applies for the mandatory information required to be printed on the lamp package (rated lumen output with the largest font, lamp power, lamp life in 165/15min scheme, number of cycles in 15/45(?)min scheme, color rating and rated voltage and socket).
Other information must be published in a lamp catalog (few spots from the mortality curve, ...) and there could be some other, non mandatory information, like e.g. the application specific life rating (like the 1/3min for the PIR's).

I know Osram was very "creative" with specifying 500000cycles or so on a plain PTC controlled preheat CFL's, but after the regulation came in force, the same lamps suddenly became 10000cycles/16000hour rating, that is quite strange...

merc:
Here's another example I've just posted. It's definitely not a pre-2009 product and they specify 100,000 switching cycles both on the box and on their website.

The EU legislation may require something but might not enforce it (by penalizing producers, for example) so they specify more realistic (or better looking) values...?

But back to:
--- Quote from: Medved on February 07, 2014, 04:08:38 PM ---The halogen lamps offer longer life, but due to positive temperature coeficient of the tungsten resistance the filament tend to heat up unevenly during the startup and some say even overheat, causing the tungsten to recrystallize, so loose the strength and for the next time make the unevenness worse, so with frequent switching the lamp life becomes very short. Mainly the lower wattage 230V (100W and below, so with a thin and long filament) are the most affected.
--- End quote ---

If this value is true (and they specify the same value even for a 230V / 28W lamp with a very thin filament), the problem with recrystallization might not be such a big problem. Could be interesting to prove these switching cycle values in an independent lab. ;)

Medved:
Beside the official rating suggest no influence of the switching to the lamp life, real life tells something different.
The recrystallization effect will be strongly dependent on the impedance of the mains connection: Higher impedance means softer startup, so less severe overheating. Here I suspect the way such tests are usually performed: A test population is mounted in a rack, many bulbs in parallel and for the setup simplicity controlled by one common cycler switch. But that means all the lamps start at once.
While when the lamp is alone, the inrush current (6A or so) is not able to influence the mains voltage, when you start 100's lamps at once, the current becomes in the kA range, so becomes pretty potent to briefly reduce the mains voltage at the point of connection. The result is, the lamps are started "softer" during the test, compare to the real life operation.
And in the real life, the problem strongly depends on the mains impedance: If two lamps are connected in parallel, the inrush current of 12A could cause quite significant drop on the wiring (10V is already a difference here), so the lamps then start more softly , so last longer than in other installation, where the mains voltage is way more rigid.
And other aspect: The larger power lamps have way higher inertia of the filament, so tend to warm up more evenly, so the problem affects mainly the low power models...

And for the Emos lamp I haven't found any cycle life specification on the box (I have few just in front of me - used as a "fuse" for small ballast tests)
That is acceptable, when no degradation from switching cycles is anticipated (and that is the general belief about all incandescents)
In the web offering they specify the 100k cycles, but without reference to any standard nor test scheme, so it could mean anything...

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