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Can someone tell me more about this transformer? Answered

Recently, I got a large high voltage transformer. It used to be part of a photocopier, and lets out 1/4 sparks when you brush the primaries on a 9 volt battery. However, I don't really know how to build a driver for it. Can someone help me out?

Here is what I know about it:
It has 7 (8 if you count the one connected to the core) leads. 5 of them are for the primary and secondary coils, but I don't know what the other 2 do.
The resistance between the two primary leads is 1.8 ohms (1 when connected to the center tap).
The high voltage output lead has a 30,000 VDC rating printed on it.
Can someone help me build a driver for this?
Edit: I have a little florescent tube driver that runs on 12VDC. Can I use this to power the transformer, or is that an idiotic idea?


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Best Answer 9 years ago

You take good enough pictures to find a blogger on the xfmr.
And a pointer to a basic inverter schematic and explanation.


Josehf Murchison
Josehf Murchison

8 years ago

That is a flyback
Look up flyback drivers and testing flyback transformers.


9 years ago

Unfortunately, this is pretty close to "Hi, I have a black box...".

Start by determining which leads attach to which coils. Sounds like you've done that. The green wire is ground for the transformer frame. It is *probably* not electrically connected to any of the coils.

Then you need to figure out what the relationship is between those leads and the coils. Resistance really won't tell you much. Inductance might... but a more direct way to probe this might be to put a small sine-wave signal across a pair of leads of the primary and measure the ratio between the input signal strength and the output signal strength; that would tell you the relationship between the number of turns in each coil. Repeat this for each pair of taps, and you should be able to get a decent sense of how much step-up or step-down you could get from the beast.

That _won't_ tell you how much current you can put through it before burning it out. For that you'd need actual manufacturer specs.

That's about as much help as I can offer.


9 years ago

yes you can use the driver that runs on 12vdc is this transformer uses high frequency. i have 2 like this at home along with its driver.

What i can deduce is that it is a multitap transformer which outputs the following which was written on mine

and i think that the others are feedback windings.

search for "555 astable driver mosfet" on google.

the picture below is the transformer with its driver. i have another one which looks exactly like yours but i can't find it