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Advice on these Chinese DC - DC converters?

SO, I got a couple of these 80w DC - DC buck converters to supply power to Houston.  One is going to be the 5 volt supply for the servos, the other is going to be a 7.2 volt supply for the Rover 5.  Last night I got a motor out and adjusted them to the proper voltages.

The thing that's got me confused is the "constant current" part.  There are two multiturn pot type adjustments.  When I ran the motor, it pulled about 350ma turning the current pot didn't seem to change anything.

I have a similar 100 watt boost converter that will be supplying power to my SBC at 18v 5a.  I figure I can connect a 100w 4 or 3.5 ohm resistor to that one and make sure it works safely, but I'm not sure how to go about setting these up to power an arduino, a D4CMC, and some servos.

Here's the manufacturers page in Chinese

Here's the ebay page.

Here are a couple of pictures

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Unlike the CV setting where you dial up 5V on the pot and you always get 5V from the output, the CC is more like a current limit rather than a current setting.

The lowest you can set it to is 500mA, so because your motor was drawing less than that, changing the CC pot had no effect. Unless you feel the need to limit the current, I'd just dial the CC pot up to the max, no configuration required.

OK. . .so far this is a good thing.

One other question that makes me feel stupid for asking it--Is it safe to assume that I clockwise is the max setting? 

It's pretty likely that this is how it's been wired up, but if you get it wrong your components will just brown-out when not enough current is supplied. Using that 100W resistor and measuring the current is an even better idea.

BTW there is nothing stupid about doubting assumptions =)