I don't know the low level stuff, but I have a decent understanding of variable loads as I've read lots of homebrew stuff for the pro/cinema/home audio guys testing amplifiers.
I'm guessing their rigs are quite a bit more complex than you would need though. But they had such features as holding the input voltage to the psu constant with a variac and other goodness. Their loads also had to be stable (constant resistance). This one guy used oven elements submerged in a 5 gallon bucket oil bath. Though I'm not sure you will be dispersing that much energy.
For the load increments I would have a system like a balance weight set. A couple a 10A load, 2 or 3 5A loads, 5 or so 1A loads, and then 9 .1 A loads (rough idea) to give flexibility.
Attached is my first pass at an analog high-current variable resistor stack. The idea is that each wire can test a rail by varying the spacing between clips to achieve the desired resistance. I ran a couple of test cases, but if you were actually going to spec this thing out you'd need to decide what power ranges you want to test over and how many simultaneous rails you want to test.*snip*
That looks to be absurdly dangerous for a PSU load tester... but really cool. :thumbsup:
The key point of this whole thread is cost, cost, cost. Icrontic is not loaded with money, so the more inexpensively we can create a device that will accomplish our goals, the better.
So far Drasnor's idea is winning because it's cheap and simple, even if it is somewhat dangerous. Other ideas are certainly welcome.
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I'm guessing their rigs are quite a bit more complex than you would need though. But they had such features as holding the input voltage to the psu constant with a variac and other goodness. Their loads also had to be stable (constant resistance). This one guy used oven elements submerged in a 5 gallon bucket oil bath. Though I'm not sure you will be dispersing that much energy.
For the load increments I would have a system like a balance weight set. A couple a 10A load, 2 or 3 5A loads, 5 or so 1A loads, and then 9 .1 A loads (rough idea) to give flexibility.
That looks to be absurdly dangerous for a PSU load tester... but really cool. :thumbsup:
My Pops is a retired union electrician - he could probably build this with his eyes closed...
I'll ask him this weekend...
So far Drasnor's idea is winning because it's cheap and simple, even if it is somewhat dangerous. Other ideas are certainly welcome.