Re: Resistor vs transformer

Hi Hans, I see you have had some helpful replies ;) I take it the 120W was a typo as you just mentioned 6W and you probably meant 120V drop (230V-110V). If you do want to use a resistor instead of a transformer it is best to use a series combo of a resistor and a capacitor. But before I go any further I should state that I wouldn't recommend this approach for anything but low-power non-isolated applications. You might use this if you just needed 10 to 20ma such as in some line-powered triac circuit.

It is true that a capacitor can be used instead of a resistor but you have practically no current limiting when it comes to transients, they will just pass right through the cap and let all the magic smoke out of your components.

But I think that you probably need to detail your application a little better because it may be that a transformer solution could be better suited, but of course this depends upon your load. I sure if you provide more detail, that among the many replies you may find one you can use.

*Peter*


Weinberger Hans wrote:
Hi ... I need to convert 230V to 110V. I was wondering whether a 2.4K
resistor with the right power rating would be a more cost/space
effective solution versus a transformer. My load consumes 6 Watts.
What sort of resistor should I use? Wire wound? Carbon?

The 120Watt consumption of the resistor makes me uncomfortable. Are
there any cheap SMPS or light transformers that would work better?
.

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