Mini psu

[stdly]

I have been looking at small power supplies for a breakout board, relay and a couple fans for my enclosure.
I see things I never noticed before when looking around.
Switching / non
Regulated / non
I wonder if one is better than the other?
Do any of these cause problems with interference being in my enclosure?
I am using Gecko 202's and a PMDX 122 board if this matters.
Steve

[NC Cams]

A regulated P/S typically has more voltage available "upstream" (say 14.5) and the regulation circuit modulates the voltage to say 12vdc as the load may cause voltage to drop.

An unregulated P/S (IE: the power supply for the DC on my Bridgeport mill CNC) is unregulated at 80 vdc or so. The servo amps regulate current and the P/S is "stiff" enough to handle surge amps required. Surge is handled by robustness of the transformer in concert with HUGE capacitors.

In under-robust cases, the impedance of the circuitry will cause voltage to sag/drop if you start pulling high current from an unregulated P/S - low cost 12v "wall plug P/S's" ofter have open circuit voltage of 13-15 vdc but drop quickly to the rated 12v as the load rating is reached, current wise.

Linear (transformer) type of P/S's have magnetic fields around them. These fields can play havoc with adjacent electronics - as most magnetic fields have a wont to do.

"Switchers" (very high speed devices that literally induce a secondary voltage by switching line side voltage off and on very quickly - sort of like a car ignition induces a secondary voltage to fire spark plugs) step voltage up or down as required.

These are quite efficient and do it pretty quietly - PC power supplies are mostly switchers. "Quiet" in this case means with little if any interference - my montor is currenlty sitting on top of a PC P/S and it is NOT jittery - can't say that about the same monitor when I had it sitting near the transformer of my UPS.

The switchers don't always have the raw "oomph" of a transformer but this "oomph" can be made up with high voltage/low current as opposed to low votage/high current.

Cost wise, it will be hard to bet the affordability of using surplus AT P/S's in obtaining the needed power from house current. Transformers can be found and guys have rewired/rewound them to get what they want but I wouldn't - too much work and not enough time....

Hope this general info helps

[stdly]

Originally Posted by NC Cams A regulated P/S typically has more voltage available "upstream" (say 14.5) and the regulation circuit modulates the voltage to say 12vdc as the load may cause voltage to drop. An unregulated P/S (IE: the power supply for the DC on my Bridgeport mill CNC) is unregulated at 80 vdc or so. The servo amps regulate current and the P/S is "stiff" enough to handle surge amps required. Surge is handled by robustness of the transformer in concert with HUGE capacitors. In under-robust cases, the impedance of the circuitry will cause voltage to sag/drop if you start pulling high current from an unregulated P/S - low cost 12v "wall plug P/S's" ofter have open circuit voltage of 13-15 vdc but drop quickly to the rated 12v as the load rating is reached, current wise. Linear (transformer) type of P/S's have magnetic fields around them. These fields can play havoc with adjacent electronics - as most magnetic fields have a wont to do. "Switchers" (very high speed devices that literally induce a secondary voltage by switching line side voltage off and on very quickly - sort of like a car ignition induces a secondary voltage to fire spark plugs) step voltage up or down as required. These are quite efficient and do it pretty quietly - PC power supplies are mostly switchers. "Quiet" in this case means with little if any interference - my montor is currenlty sitting on top of a PC P/S and it is NOT jittery - can't say that about the same monitor when I had it sitting near the transformer of my UPS. The switchers don't always have the raw "oomph" of a transformer but this "oomph" can be made up with high voltage/low current as opposed to low votage/high current. Cost wise, it will be hard to bet the affordability of using surplus AT P/S's in obtaining the needed power from house current. Transformers can be found and guys have rewired/rewound them to get what they want but I wouldn't - too much work and not enough time.... Hope this general info helps

Helps! You bet I already copied it to a text file for safe keeping! Thanks for taking the time, I have it straight as to what I will do now.
Steve