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I am attempting to power an arc lamp (which I have) using a programmable power supply (which I have yet to source.) Though the lamp is rated at 1000w (37v at 27A) I would like to power it at about 800w in order to modify its emission spectra and extend its lifetime.

The lamp in question is out of production but nearly identical to an Osram HBO 1000 W/D. While the lamp housing is a modified Christie Xenolite 1000 W lamphouse fixture. The xenolite housing has been modified mechanically. The system had originally used a more modern (but still solid state) Christie power supply rather than the original rectifier power supply. We smoked quite a few caps in that power supply when we tried to fire it up. AFAIK the igniter in the Xenolite lamphouse still works but we haven't actually seen a bulb light since only the igniter works.

When attempting to source a power supply I see items like a Sorenson DCS 40-30E which can supply 0-40V and 0-30A. This seems perfect for me. Reading through the manual, it describes operating the supply in current limiting mode and voltage limiting mode. I may have misunderstood the terms but it seems to me the operation of an arc lamp requires both current and voltage be limited as the lamp will draw any "available wattage."

So, to restate the question, what is the theory of operation for a arc lamp regarding voltage/ current regulation and how does one specify this in the design of a power supply?

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  • \$\begingroup\$ Let me offer two apologies off the bat: first, sorry if this is a noob question. EE is not my strong suit. Second, sorry this is sort of a two part question. How to operate the lamp and how to choose the power supply seemed too intertwined to ask separately. \$\endgroup\$ – PhotoScientist Jun 22 '18 at 14:57
  • \$\begingroup\$ Citation from the manual about limiting current? Sounds suspicious. \$\endgroup\$ – Eugene Sh. Jun 22 '18 at 15:03
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    \$\begingroup\$ Typically you need a high voltage for ignition and a ballast to provide relatively loss-free impedance to counter the negative resistance characteristic of the arc. This might be a bit too challenging for a self-described noob, I think. \$\endgroup\$ – Spehro Pefhany Jun 22 '18 at 15:05
  • \$\begingroup\$ @SpehroPefhany the enclosure for the lamp includes an igniter which is powered independently. My understanding is that relays operated by the lamp selector circuit (a tungsten lamp is also an option) control when power to the ignitor and from the lamp power supply are applied to it. I should also note that the integration of the power supply will be done by a qualified EE and tech. I've just been asked to source a power supply and don't want to look like an imbecile. \$\endgroup\$ – PhotoScientist Jun 22 '18 at 15:13
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    \$\begingroup\$ Igniters often apply high voltage AC for starting. Mating the igniter with a separate low-voltage-high-current supply can be tricky. Your 800W DC supply may be at risk of destruction by the igniter's high voltage. \$\endgroup\$ – glen_geek Jun 23 '18 at 0:08

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