The electronic way is a constant current source shunted to ground or through a resistor bank.
One hefty npn power transistor and a few smallish components. Or a jfet with source tied to gate, with a current adjustment resistor in the source lead. Or any of a hundred circuits. For more wattage you can parallel several, each adjusted to take their fraction of the total amps. I seem to be slowly turning into a power electronics engineer over here. On Dec 31, 2014 3:42 PM, "chuck--- via Af" <af@afmug.com> wrote: > I am thinking a DC-DC converter that will take a wide input and > constant voltage output into a nice temperature compensated resistive > load. What voltage range do you want? > > Doh!, that would be a constant power load. > > You want constant current load. Have to continue thinking... > > *From:* ch...@wbmfg.com > *Sent:* Wednesday, December 31, 2014 3:39 PM > *To:* af@afmug.com > *Subject:* Re: [AFMUG] Dc electric load ? Chuck ? > > I know how to do it really cheap and easy under 2 amps. Have to think > on this a bit. I have used hot water heating elements and coils of wire > (in a bucket of water) for high wattage resistors but obviously not > constant current. > > *From:* TJ Trout via Af <af@afmug.com> > *Sent:* Wednesday, December 31, 2014 12:11 PM > *To:* af@afmug.com > *Subject:* [AFMUG] Dc electric load ? Chuck ? > > > Anyone know of a inexpensive do it yourself way to make a dc constant > current electric load for testing power supplies, lithium batteries , etc ? > Looking for something maybe 2kw+ and the cheapest premade thing I can find > is $3500. Maybe I'll just use a carbon pile load but that will be much less > accurate. >