DC Power Supply Variable 30V 10A with Output Switch, Adjustable Regulated Switching Bench Power Supply with 4-Digits LED Power Display, 5V/2A USB Interface, Accurate Encoder Adjustment Knob

I didn’t use it for high current output since it’s very light. But it keeps working without any problem if current under 4A even though the fans run a little noise. I would like you to run this with current under 3A for safety.

Although I haven't opened the case to see the quality of work put into populating the PC board, the main unit seems to be well made.Display is clear and bright (a bit too bright for my taste, but not irritating).Love having the Output control button (and it's lighted when enabled. Nice touch). That was a deal breaker for other DC power supplies I was considering.Nice not having to short the leads to set the current level.Both the Voltage and the Current displays are very accurate. Using a recently calibrated multimeter I checked unloaded Voltages between 1.00V and 28.00V. While testing a small brushless fan the displayed Voltage was 12.00V, my measured Voltage was 12.008V. The displayed current was 0.062A, my measured current was 61.73mA. I have not checked the accuracy while using more demanding loads.Changing the output V and A is simple and intuitive (push the adjustment dials to change range). I wish, though, that the selected range would be remembered when the unit is powered off and powered back on. It defaults to the lowest digit.The supply was quick to respond when Voltage levels were increased (e.g. from 5V to 10V). However, (and my only complaint, albeit a VERY minor one) the unit did not respond as quickly when the Voltage was reduced, most noticeably below the 10V level, and increasingly so as the level was lowered further. For example: Changing from 10V to 9V was sluggish: took approx. 1/2 second to settle. Changing from 2V to 1V took approx. 3 seconds. However, in all fairness, those measurements were taken without a load. The levels changed much more quickly under load, which is what really matters.I'll return for a follow-up review after I've used the supply for several months. But so far it's a very nice unit for my use (small electronic projects). Well worth the price, in my opinion.

This is the third revision of this review and I hope it’ll be the last. The first review was on done October 29th, 2022 where I gave it 3 “Amazon-Stars”, but in reality, it deserved 3.5 stars. In the second review on May 13th, 2023, I gave it 2 “Amazon Stars” but in reality, it deserved 2.5 stars. In this review, I’ve added some critical tests that should’ve been considered in the previous reviews. Namely, Voltage Regulation and I re-tested Accuracy & Ripple. It’s changed my opinion of this Power Supply considerably for the better, & has improved the Amazon Star Rating from my last 2 reviews. I took 3-days to thoroughly test this Power Supply scientifically and write the review. This review is MUCH MORE accurate & comprehensive.My qualifications for this review: Simply stated, I’m a degreed Electronics Engineer with a B.S. & a Masters in Electronics Engineering from Caltech. I’ve been working in the industry for the last 37yrs at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, CA. I started in electronics when I was 15yrs old. I’m not boasting here. I’m simply level-setting that I know of where I speak.I bought this Power Supply back on July 30th, 2022. It’s now January 21st, 2024 (1yr 6mo.) so, I’ve been able to put it through “it’s paces”. I bought this Power Supply after reading the reviews. It seemed like a decent enough supply to put on my bench at home for some simple, non-critical prototyping. I’m framing this review for the “Electronics Hobbyist / Enthusiast / Professional / Engineer” in mind and for no other purpose. I will examine 4 main areas:1) Operational Effectiveness2) Accuracy3) Voltage Regulation4) RippleOPERATIONAL EFFECTIVENESS:It's well constructed. The cabinet is made of a heavy gauge metal. It comes with a standard North American appliance cord; Output Cable with Banana plugs & alligator clips and of course a manual. It was packed well by IKococater with it securely suspended between 2 Foam Rubber supports and wrapped in a protective heavy plastic bag. I'm impressed with the warranty; "Guaranteed for Life”! (You don't see that very often). To clear up some confusion on the Green Connector Binding Post as noted in other reviews. This is a physical "EARTH" ground. NOT a "NEGATIVE" voltage. Speaking of binding posts, standard spacing between Binding Posts is 3/4" (19mm) with positive and negative side-by-side. This is in order to accommodate the use of double banana plugs (Pretty important, especially in electronics). This power supply does not conform to either standard in this regard. This is disappointing. The operation of the unit is mostly straight forward for voltage & current settings. The unit has 2 power buttons on the unit. (I have no clue why!) One Rocker Switch on the back of the unit, and a Push Power button on the front. The Push Power button on the front would've been sufficient. The unit also has an internal cooling fan. During the whole time I’ve owned this, the internal fan has NEVER “Kicked-In”. (But then again, I never really demanded that much power from it) I discuss internal cooling later in this review. The Voltage & Current adjustment knobs use Rotary Encoders which provide continuous detents (nice). But beware, if you rotate the knobs too quickly it won’t register the “click(s)”. (Just use a smooth rotation, it works perfect). This series of power supply is a "Constant Voltage / Constant Current Automatic Conversion Type". Which means: it will change between Constant Voltage OR Constant Current mode with load changes. For the novice in electronics this could become very frustrating to control & understand (Be aware!). The displays have large bright white LEDs for viewing. It would be nice if this had more weight. (But you won't find weight in a "Switching" type power supply due to the missing large Step-Down Transformer). If you plug the Banana Cable in to the Binding Post, the unit will move, or even tip over if you're not careful. This has a very convenient/handy USB Port in the front of the unit. I “knocked-Off” 0.3 stars because the Microcontroller can’t keep up with real fast turning of the Rotary Encoders, and 0.7 stars because of the lack of standard conformance with the spacing of positive & negative Binding Posts. Therefore I give OPERATIONAL EFFECTIVENESS an “EXECLLENT” grade (4.0-Stars)So, let’s get to the "meat"...ACCURACY: (Photos attached)Unlike other reviews, I took 9 voltage samples. [NOT just 1, that is not a test of accuracy] Equipment used to measure voltage was a Siglent SDM 3055 Bench Multimeter with 5.5 digits of precision that was just recently laboratory calibrated. Overall, this Power Supply provides good accuracy on voltages between 0.8v to 30v. Once you go down to 0.7v and lower, [being less than 98% accurate] the accuracy falls off sharply. But from a practical standpoint, how many circuits do you need to power less than 3.3v though?NOTE 1: These measurements were NOT taken under load. I’ll get to Voltage Regulation later in this review. [Where voltage measurements ‘WERE’ taken under load.]NOTE 2: The manual doesn’t specify the accuracy of this unit. So in lieu of that, typically accuracy specifications that are widely accepted in the industry have a voltage accuracy of +/-2%.With that said, being that this doesn’t have a 98% accuracy for voltages less than 0.8v I CAN'T give it 5 stars for accuracy. But I can still give ACCURACY a “EXECELLENT” grade. (4.9-Stars).VOLTAGE REGULATION: (Voltage Tests under Load) – Photos attachedTo perform these tests I used a Siglent SDL-1020X-E Programable DC Load. (200Watts). I performed 2 sets of tests that were at 5.0v & 3.3v. (The most commonly used voltages in electronics) Each set of tests I tested at 0.5A increments up to 5.0 Amps. (Please see the attached screenshot of the Performance Curve)5.0v performed VERY GOOD at 95.35% Efficiency. Meaning; it held Voltage Regulation very well.3.3v Also performed VERY GOOD at 92.89% Efficiency.Typically, you want to see 96% or higher. But at 95% & 92%, that’s pretty good for a $60 Power Supply! Therefore, I give VOLTAGE REGULATION a VERY GOOD Grade (4.4-Stars)NOTE: I performed a test to see when the internal fan would “Kick-In”. I set the Power Supply at 30v and increased the load in 0.1A increments up to 5A. It didn’t “Kick-In” even after keeping it at FULL LOAD for more than a minute. Odd…RIPPLE: (Photos attached)Given that this "is" a "Switching" type power supply, it's not surprising that it has some noise, and that's to be expected. The specifications CLEARLY state: RIPPLE NOISE: <= 50mVrms (and that’s where it should be). I also want to note the conditions of how I measured RIPPLE:NOTE 1: I used a Siglent SDS1202X-E Oscilloscope. (Recently laboratory Calibrated)NOTE 2: I took 2 measurements (with photos); One where it was NOT taken UNDER LOAD and the other with it taken under LOAD; 5v @ 5A. I took the measurements directly off the Power Supplies' Binding Posts.NOTE 3: <most importantly> I used a ‘M’ BNC Oscilloscope Probe Adapter(s) & a “Pomona” ‘F’ BNC to Banana & Hook Test Leads on the Oscilloscope Probe. This is the best possible connection to give the “FAIREST” test possible so that external Transients are not introduced and won’t skew the measurements. This is why I didn’t use the supplied Oscilloscope Probe “Ground Wire” to Alligator clip.(FYI: The Ground Wire on Oscilloscope Probes act as an Inductive Antenna – in case you didn’t know)FYI: The “<= 50mVrms” per the Mfr. specification, really doesn’t mean anything without knowing under what conditions you would obtain that measurement (e.g. Bandwidth, Load, Voltage, Current etc.) Because they really don’t want you to know what the Pk-Pk is. That’s a dirty little industry secret BTW.FYI: I would like to point out “Acceptable” ripple voltage is about 100mV Peak-to-Peak. “Switch Mode Power Supplies” (SMPS) (This one I’m reviewing), figures of 50mV Pk-Pk or less “are possible”.I configured the Oscilloscope as follows:COUPLING: ACBANDWIDTH: 20MHzPROBE RATIO: 1xACQUISITION: PEAK DETECTIONFFT (Fast Fourier transform)Algorithm: HannigResults: NO LOAD (after 14,734 samples)No load performed pretty well.Peak to Peak (Min): 40mVPeak to Peak (Max): 360mV (That’s a High Peak !)Spike: 132mV @ 244.14kHzPeak-to-Peak Mean Avg: 96.75mV (Within accepted industry norms)(The Mean Avg is directly correlated to the Spike occurring EVERY 4.096us (microseconds))mVrms: (Min): 7.65mVrmsmVrms (Max): 62.89mVrms (not exceedingly bad – within industry norms)mVrms Mean Avg: 28.60mVrms (Better than Mfr. Specifications by a wide margin!)Results: FULL LOAD (5v @ 5A) (after 14,011 samples)Under a full load DIDN’T perform NEARLY as wellPeak to Peak (Min): 148mV (Above the accepted industry norms)Peak to Peak (Max): 390mV (That’s a High Peak !)Spike: 161mV @ 122.07kHzPeak-to-Peak Mean Avg: 273.29mV (VERY HIGH – FAIL!)mVrms: (Min): 24.24mVrmsmVrms (Max): 60.15mVrms (not exceedingly bad – within industry norms)mVrms Mean Avg: 39.65mVrms (Better than Mfr. Specifications)It was fully expected that Ripple will be greater under load. In this case, the Pk-Pk voltages were FAR ABOVE industry norms. But on the upside, Voltage RMS stayed within Mfr. Specifications.I give RIPPLE an “OK” grade (3.0-Stars) – “Nothing to write home about”PRO-TIP: (Photos attached)If you’re working with 5.0v circuits (3.3v circuits in particular), those circuits are generally far less tolerant of huge spikes and huge ripple. If you require / want less Ripple and Transient Noise in the output, and you don’t have the funds to purchase a “Lab Quality” LINEAR Power Supply; simply add a Filter Capacitor or a Capacitance Multiplier(better) at the output EXTERNALLY. (Capacitance Multipliers are cheap and easy to build (less than $5 in parts) You’ll NEVER get rid of 100% of the RIPPLE, but you can get rid of “MOST” of it. Check the “After” photos of Ripple when I added a Capacitance Multiplier. “ALMOST….” PURE DC!Ripple Noise (Peak to Peak): 38.00mV !!Ripple Noise mVrms: 4.87mVrms !!This calls into question just one thing: Why couldn't IKococater add 3 additional parts worth $4.14 leading to the output, to smooth out the Ripple and make this a 5-Star Power Supply? (Too bad)CONCLUSION:Overall, this is a nice little supply for the “Electronics Hobbyist” or the student that’s learning electronics, or who works with Arduino, Raspberry PI etc. this Power Supply will work very nicely. For the Electronics “Enthusiast”, who’s looking to build more advanced circuits, that may require greater Current delivery or better Ripple characteristics then….. maybe not. (Depends on the situation). For the Professional dealing with RF, or that require much better accuracy and better Ripple characteristics, ABSOLUTELY NOT…FULL STOP.Operational Effectiveness: (4.0-Stars)Accuracy: (4.9-Stars)Voltage Regulation: (4.4-Stars)Ripple: (3.0-Stars)Without “weighting” on any particular metric, I give this Power Supply 4.08-Stars which I feel is a fair & objective review. I REALLY wanted to LOVE this supply. If it hadn’t been for the Ripple, this could’ve been a 5-Star review.I know there's a lot of 5-Star reviews on this Power Supply. You see the numbers for yourself in addition to the attached photos. I'm sure you'll agree this IS NOT a 5-Star Power Supply.I don't "LOVE" this Power Supply, but I do "LIKE" it, and I would recommend it for certain applications.As I said before, if you want to improve the Ripple then add a Capacitance Multiplier! I hope I’ve given the readers of this review a way to make an “Informed Decision”.

I’m very impressed with this power supply. Not only does it have very accurate and fine control of the output voltage and current up to 30v, it also has a USB output. This is a game changer as it means I can power say an arduino from the USB, and motors or other higher voltage/current direct from the power supply. Normally when working on projects such as this I have to power the arduino or controller board separately so this makes my desk tidier which is much appreciated.The adjustments on this model are a lot finer than I’ve seen on power supplies such as this. You click the dial then adjust each digit individually. This is nice because other models just have a dial and you end up overshooting the value you want and trying to fine adjust it to where you are and it’s difficult some times.This power supply came well packaged, well protected and super quick. It came with the hook up connection leads and a power cableAll in all, a great power supply with some nice features. I’m very impressed for the price.