Re: Limiting current, w/wall wart txformer?

Generally, the easiest and cheapest (possibly not the best, though) solution for limiting current is the LER light emitting resistor, aka incandescent lamp, light bulb, bulb, bub etc.

The light gives a visual indication at-a-glance that the circuit or device is on and/or operating.. it doesn't get much better than that.

Measuring the current in the circuit with the lamp on (with the filament hot), will confirm that the circuit current falls within the desired level.

I have a number of lamps in a drawer with their currents (x-mA @ x-V) marked on them with a label and a Sharpie marker, because I don't care to (and probably couldn't anymore) remember what their operating currents are.
Choosing a particular lamp number/type for a current level will usually be very close to one in the drawer, as lamp characteristics are fairly well standardized.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


<vrgolf@xxxxxxxxxxx> wrote in message news:r8lkl4t0u4gchpqboglci2jqar2qi65jm3@xxxxxxxxxx
Lost a txformer/charger for a battery powered unit.
Odd specs, 200ma, 12V. Also has an unusual plug.

Found a 700 ma, 12V unit in the junk drawer, and the plug
fits!


As I don't particulary want to destroy the battery, limiting
current would be nice.

This is assuming that finding a 200ma 12V unit w/the
appropriate plug would be tougher.

Suggestions appreciated.

thanks

gary


.

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