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Re: BENCH POWER SUPPLY - Help!
DO NOT POWER ANY BIG MOTORS OFF OF THIS SUPPLY.
The key point about your bench top supply is that it is a switching regulator. This means that its output looks like a diode followed by a capacitor. Therefore, it will only supply power, it will not sink power.
This is all well and good for powering your control system, as it (should) never attempt to push power back into the supply. However, remember that a DC motor is also a generator. If you were to run a heavy motor full forward and then stop, the energy that is held in the shaft will get pushed back through the victors to your supply. The capacitor will attempt to soak that current, but its voltage will shoot up. The diode will then be reverse biased, effectively eliminating your supply from the circuit.
The end result is that your 12V rail just jumped to some unknown value. If this new voltage is high enough, badness 10000 will occur.
I haven't managed to do this with the KOP, but I've done it before quite painfully on another project. Typically, this will occur while you are presenting.
If you have them laying around, a couple FHCs (Freaking Huge Caps) can help mitigate this, as well as handle the kick over problem.
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