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External 5V power supply needed... not computer PS
knohbody:
--- Quote from: DaOld Man on September 19, 2010, 05:58:09 pm ---I have a arcade power supply that came out of a cabinet I bought.
It has +5VDC at 11 amps, -5VDC at 1 amp, and +12 VDC at 2 amps.
My current project needs 5VDC at around 5 amps, so this PS should work for that. My problem is that my project also needs 24 VDC at around 0.5 amp.
I can get 17 volts by using the -5 and the +12, but I must have at least 18 volts (24 being more desired).
The PS has an adjustment on it and I can crank it up to get a little over 18 volts, but that runs my 5 volts up to above 6, which is not desirable.
Is there a similar power supply that supplies 24 VDC along with 5?
Also, there is a terminal marked FG on the power supply, what is this for? It was connected to GND, but PS seems to work fine disconnected.
--- End quote ---
FG stands for field ground. It's for the A/C input from the wall, and should never be hooked up to the D/C ground line. As far as finding a 24 vdc power supply similar to the one you have, this one from happ should work.
http://www.happcontrols.com/powersupplies/42pp068.htm
gryhnd:
--- Quote from: DaOld Man on September 19, 2010, 05:58:09 pm --- My problem is that my project also needs 24 VDC at around 0.5 amp.
--- End quote ---
I picked up one of these for my juke project to step up my 12V PSU to 18V for a particular compenent. I haven't got to the stage of using it yet beyond making sure it worked as expected:
http://cgi.ebay.com/12V-24V-DC-DC-Step-Up-3A-Power-Converter-Module-/220594615570?pt=LH_DefaultDomain_0&hash=item335c76b512
* Input: 3.5V - 40V DC
* Output: 65V DC, 3A
* Regulation range: 5V - 55V variable output
* Internal oscillator: 52kHz
* Board dimensions: 48 x 35mm (1.9 x 1.38")
DaOld Man:
Thanks for the info guys. I THINK the FG was jumped to ground, but I could be wrong, two of the grounds may have been jumped together.
I like the arcade power supply, but it's pretty high (cheapskate alert!!).
Plus I already have one that just isnt 24 volts though.
The DC to DC converter looks pretty slick too. While I was checking it out over at ebay, I came across this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170431340884
And bought it. A little over 11 bucks and free shipping.
So I really liked the idea of having both power supplies in one package, but this wont be too bad, and I will have 12 VDC from the arcade one I already have, should I need it for something else.
Hopefully the two power blocks will look neater than the old computer AT power supply I was thinking of using.
Again, thanks guys!