Recently bought a Xantrex XDL-35-5:
I have this Xantrex XPF-350 dual supply on order but don't have yet:
I just received a Kepco XLP-150-16-1200:
A Protek 1805 and 3040T:
Haven't looked closely at noise yet, but here are my reviews:
The Xantrex XDL-35-5 is truly high grade. The interface is easy to use. The precision is excellent. I love the ranges of this supply. The500mA current range with 0.1mA resolution is great for evaluation of LED light sources. The only thing that's wierd is that the supply outputs a few negative mV when the output is turned off which produced a few -mA into my meter when I was measuring current. It was about 0.014V 0.007A or vice versa, I forget. But since the voltage was very low, I doubt it could actually do anything annoying, unless you were operating is as a voltage reference. In that case, better to leave it turned on at 0.000V.
I anticipate the Xantrex XPF-350 will be equally impressive.
The Kepco, at 1200W constant power and able to reach 150V*8A or 75V*16A, compares to only one other product on the market, the Agilent 6030A. The Kepco however lists for $1795 while the Agilent is >$5000.
The Kepco is a little bit awkward. The knobs increment the V/I settings in large non-decimal increments. I quickly discovered though, that pressing the knobs accesses a fine adjust which allows setting to the full display resolution. The only other annoyance is that it sounds like a vacuum cleaner. Well, almost. It's way too loud to be unannoying if it's just a few feet away. I was almost set to send it back and look for another brand until I noticed the price on the Agilent. Now I think it's not so bad for the money. I may just try to swap out the three fans inside for quieter ones.
The Protek products are inexpensive and of "reasonable" quality. I bought two for home. I also bought two for work. I received only my personal copies as of yet. The 1805 works fine (used it to trim my beard this morning). The 3040T buzzes quite a bit in the power transformer. I don't like that, so Tequipment.net will be replacing it. Hopefully the replacement will be Ok. A coworker has a Protek 3033B and it is fine. They have a 2 year warranty which is a plus.
I wish I had the money for the two Xantrex supplies for my home use, but a total of $2000 is just not a wise use of one's meager allowance when I only get a few hours now and then to play. I'll have to settle for the budget brands.
Summary: Very impressed with Xantrex and will buy more in the future. Kepco looks like a good workhorse, just need to put it in another room. I suppose I can control it with a LabVIEW Vi or something, since it includes all the interfaces standard, which is cool. Protek--good enough for general purpose breadboarding and experimenting, for which it has better useability and feature/price ratio than competitors like B&K, Instek, Extech, Sorensen, etc.
We need a web site for test equipment reviews!