Author Topic: My thinking about a hot restrike show of the american or japanese SBMV lamps  (Read 367 times)
dor123
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My thinking about a hot restrike show of the american or japanese SBMV lamps « on: June 03, 2012, 10:10:45 AM » Author: dor123
Regarding to the conclusions I drew, I think that a hot restrike show of a 120V SBMV lamp would be the same as the neon based HPS retrofits for mercury lamps (Ie. after turning the lamp off and back on fast, no glow or discharge will be produced by any means and no current or voltage will flow through the lamp, until the thermal rely closed, and than the lamp will lit instantly and directly from no glow at all). I understood the following things about american and japanese SBMV:

As the american and the japanese mains voltage is 100-120V, unlike in 220-240V countries, mercury lamps in Japan and North America can't ignite directly from the mains voltages. Because of this reason, american mercury lamps, unlike the european ones, ignites, not from the mains, but from the OCV of the ballast itself (This is the reason why american ballasts are autotrasformer ballasts [ie.. HX and CWA and not Chokes]).

However, a problem arise with SBMV lamps in america, which mush have the ability to strike directly from 100-120V, because the filament is just a simple resistive ballast without own OCV (Like choke ballasts).

The solution is to eliminate the starting electrode, and to preheat the main electrodes itself by an external heating source (Similar to how fusers of copiers and laser printers are heated, this is necessary because a real preheat MV lamp with self heated filament type electrodes like in fluorescents, would require a complicated construction and will be horribly expensive), which in this case are tungsten filaments near them. The tungsten filaments preheats the mains electrodes, and after a 30 sec to 1 min, a thermal rely, opens and break the contacts through that filaments, and produces the necessary voltage to ignite the arctube (This is the same principle operation of a thermal starter [Like the one in Eltam Perfekt-Start ballast]).

Because there are actually no starting electrodes and because of a presence of a thermal disconnector (The thermal starter) inside the lamp and the low mains voltage, when the lamp is turned off and back on fastly, the lamp will totally extingush with no discharges and ignition trys, and will remain such for several minutes, until the thermal rely will be closed and the lamp will restrike instantly (The main filament will lit, and the preheating process of the cold striking will be repated, but it will continue for a much shorter time of a few secs.
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I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the European date format (dd.mm.yyyy).

I lives in Israel, which is a 230-240V, 50hz country.

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