Re: micro wire-edm project (and software solution)

> A current sense resistor has to be able to handle the total current.
> diodes are cheap in comparison. They have a high voltage drop which
> is not always a good thing, but can make monitoring the current easy.
> But, did I mention they are cheap ?
>

I am still a little confused as the voltage drop over a diode will be
its forward voltage and that is not normally very large. The voltage
drop will not be proportional to current and as you would still need
to limit the current you could use the current limiting resister.

> Many of the low end RC EDM machines use them as the sense voltage

source.

So they are not using them as a voltage references?

I will probably measure gap voltage anyway to be quite honest and if I
were to use a shunt it could be a tiny value, at the low intended
currents it would not need to be all that big or expensive.

Graham