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Load sensing circuit

I have several switch mode supplies that are supposed to power a commercial inductive lamp, via coupling coil/socket, at 2MHz 300VAC. I do not have the lamps or coupler, but need to use the supplies for another purpose. However, they show no output on the CRO.

It is unlikely they are all bad. So I am wondering, is it conceivable the supplies would incorporate some kind of sensing circuit to prevent operation when not connected to the intended load?

If so, what would be the best bet for getting around this? IOW simulating the loading of the lamp and its coupler.

Thank you for any suggestions.

Ed Williams

Reply to
Ed Williams
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It is possible the supplies are expecting the inductive load as part of an output series resonant circuit as commonly used in electronic ballast circuits...then you get no output without it.

Reply to
Fred Bloggs

"Fred Bloggs"

** LOL.

Inductive lamps are not.

The full name is " inductively coupled, electrodeless, gas discharge lamp ".

....... Phil

Reply to
Phil Allison

The OP says the lamp requires a socket with a "coil"- that coil is almost a certain necessity for the driver circuit, itself a half bridge series resonant architecture...

Reply to
Fred Bloggs

"Fred Bloggs"

** The OP is a fool with no clue.

YOU are making wild guesses.

A series resonant cct is non inductive at resonance.

It ain't a ballast.

Go away.

..... Phil

Reply to
Phil Allison

So I should try winding an air coil and keep adding turns until something clicks?

Where should I start, given the rated 2.5MHz output of the SMPS?

Ed Williams

Reply to
Ed Williams

Oh, I just noticed from specs the lamp socket/coupling has a cylindrical ferrite core built into it. I suppose then I can wind a coil onto this, ping it with a 2.5MHz signal and watch the CRO for resonance.

Ed

Reply to
Ed Williams

It's no secret how these drivers operate as there is a copious amount of information published in the application notes and patents. They are all in fact half bridge series resonant oscillators. Too bad for you, you do not regulate the dissemination of the scientific and engineering literature, so that, unlike the clueless adolescents and newbies you habitually attempt to bully with your superficial and non-informational pretense of expertise, we do not have to rely on you in the slightest.

Reply to
Fred Bloggs

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