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Unread 14-10-2012, 20:16
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Re: 110V AC to 12V DC suggestion

Quote:
Originally Posted by Mr. Lim View Post
I'm reluctant to share this actually...

...but a blade server power supply could potentially be used for this.

They show up on eBay for well under $100 quite regularly, and push out over 175A at 12V.

David Edwards, a mentor for 1310, and I have thrown around the idea of modifying one of these to power a functional FRC robot.

But truthfully, I have never pursued it, because I simply don't trust myself enough to modify something that puts out that much power.

If you have an experienced power electronics engineer at your disposal, then maybe you could safely give this a shot.

If not, please do not try this at home!
Using a single blade server power supply won't work for a stangard FRC robot since A CIM can pull 132 AMPs at stall (which is where motors start at) and there are typically 4 of those plus other motors.

Sistering (pairing) these power supplies may or may not be possible depending on their overcurrent protection. Most overcurrent protection detects a high current (low output resistance) and shuts down the output, then will periodically turn back on the output and re-check for overcurrent. This results in a periodic pulse (normally called hiccup mode) on the outputs until the overcurrent is removed.

If there is no overcurrent protection on these supplies then pairing is possible using "or-ing" diodes capable of more than the supplies output (typicallly 50% or more). These work by having the power supply with the highest output voltage supply all the current until its output voltage sags to the level of the next highest supply, at that point both supplies share the load until they both sag to the level of the next supply (et cetera).
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