switchmode PS rating
switchmode PS rating
(OP)
On a standard computer switchmode Ps i have, it is rated at 30A @ 5V, 25A @ 12V... etc. are these ratings total Eg, 30A
Max at 5V, with nothing on the other voltages, or can it supply 30A @ 5V, AND 25A @ 12V simultaneously ?
Ken
Max at 5V, with nothing on the other voltages, or can it supply 30A @ 5V, AND 25A @ 12V simultaneously ?
Ken





RE: switchmode PS rating
I would say the MTBF (Mean Time Before Failure) would be a straight line going from maybe 200Hrs with full load, out to 5 years with no load. (seat of the pants).
Also a lot of people presume to use them for non-PC applications, and while possible, you must remember that PC power supplies are totally, (consumer), optimized for just specifically; 'the job'. Every fractional cent, (or yen), has been bred out of them for years, with otherwise nutty concessions made, 'because they can', as the application is so specifically understood. They are truly thoroughbreds for their jobs. Note: You can't use a race horse to pull a sled of logs.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: switchmode PS rating
It says
+5V 25A
+3.3V 6A
but they are bracketed together with a 125W max rating.
5x25= 125
3.3x6= 19.8
Total would have been 145W if not otherwise stated.
Like itsmoked says, they are tuned for cost. Typically a motherborad would use less 5V power if it used 3V3. It is called a 300W peak unit and yet the sum of the power rail ratings is actually only 260W.
RE: switchmode PS rating
So it is possible to pull maybe 50A using only the 5v rail? for a limited amount of time?
Yes your correct, it is being used in a current controlled power supply, up to 30 amps @ 5V for hard chroming.
Next prob it to calibrate the amp meter....
Ken
RE: switchmode PS rating
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: switchmode PS rating
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: switchmode PS rating
itsmoked, youve already answered my next question,
mainly out of cuiosity,and being how i am, can you explain why 2 switchmode PS cant be used in parallel?
Ken
RE: switchmode PS rating
There are ways but they often cost energy or, the supplies need to be designed for sharing.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: switchmode PS rating
my limited electronics knowledge tells me if there was a diode in the outputs, there could be a chance of them working together?? Voltage drop isnt an issue.
I would prefer to use a transformer for the supply, but to find one with a large Amp rating, and at a realistic price (yeah in cheap, but also love to build all my own equipment) is proving to be the sharp pointy thing burried within cut folage:)
RE: switchmode PS rating
Best is to ebay the supply you need. That way you can probably get voltage and current control.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com