Good power supply? - Page 1
Forum section: electronics / testgear

author: 5370H55V
author_rank: Contributor
timestamp: April 16, 2020, 04:54:17 pm
content: Hi all, I'm looking to purchase a benchtop power supply for my home lab for under $250 if possible. I've started looking into buying older supplies like the E3630A since it seems like I can get a better supply for my money, but what are some other options in my price range (both new or used)?Any issues I should be aware of or look out for when buying older power supplies?

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 04:58:02 pm
content: What functionality do you need? How much ampules? How many voltages? Will you need multiple outputs? What about getting an old ATX supply and modifying? Constant current?Nobody knows what you need, or what your definition of "good" is. Only you.

author: nctnico
author_rank: Super Contributor
timestamp: April 16, 2020, 05:37:52 pm
content: IMHO an HP/Agilent 66311B (or similar) could be a good option (after mounting a Noctua fan in it).

author: wraper
author_rank: Unknown
timestamp: April 16, 2020, 05:54:05 pm
content: Quote from: nctnico on April 16, 2020, 05:37:52 pmIMHO changing 2 resistors in fan control circuit works better based on my experience with 6612C (I replaced fans too). Also if it's made similar, there likely is one internal VREG heatsink which runs very hot (like over 100oC) if fan speed reduced to make it quiet even though main heatsink still remains cold. So in the end I made it run significantly louder than I would like, though incomparably quieter than originally.

author: rvalente
author_rank: Frequent Contributor
timestamp: April 16, 2020, 06:10:47 pm
content: Supplies I use, like and would recommend (altought do not know their needs)66332A - 20V 5A6633A - 50V 2A62 seriesIm sure with those (and many others) you just can't go wrong

author: Grandchuck
author_rank: Super Contributor
timestamp: April 16, 2020, 06:12:53 pm
content: Lots of those available on ebay! Also, it appears that the schematics are available too:https://www.eevblog.com/forum/testgear/schematic-for-agilent-e3630a/msg348279/#msg348279It is a bonus to have test gear that can be repaired.

author: 5370H55V
author_rank: Contributor
timestamp: April 16, 2020, 06:23:25 pm
content: Quote from: engrguy42 on April 16, 2020, 04:58:02 pmI'm looking for a linear power supply with a digital display that can provide at least 1A at 24V, with one more 5V or 6V rail. This means a dual output supply is fine if it goes 0-25V, or a triple if it has two 0-20V rails plus a 6V. I have not considered modding an ATX power supply, how do they compare? I thought most of the adjustable voltage conversion kits use a switching regulator to control the output?

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 06:27:27 pm
content: An ATX typically is a switching supply that has 12v, 5v, and 3.3 v, non adjustable, and with no constant current stuff or digital display unless you add all that. So it sounds like that's off the table for you.

author: rvalente
author_rank: Frequent Contributor
timestamp: April 16, 2020, 06:29:01 pm
content: Agilent E36 series, a bunch of models. Search on ebay

author: Gyro
author_rank: Super Contributor
timestamp: April 16, 2020, 06:31:49 pm
content: Don't even think of going for some ATX PSU lash-up. You have the budget for aproperdual channel linear bench PSU (and your needs sound modest) so that's what you should buy.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 06:42:33 pm
content: Quote from: Gyro on April 16, 2020, 06:31:49 pmWow. The arrogance.Gimme a break. ATX supplies are perfect fine for tons and tons of users. Geesh.

author: tautech
author_rank: Super Contributor
timestamp: April 16, 2020, 06:45:27 pm
content: Quote from: engrguy42 on April 16, 2020, 06:42:33 pmNope, wisdom and experience.

author: tautech
author_rank: Super Contributor
timestamp: April 16, 2020, 06:48:16 pm
content: @5370H55V~$100 more than you wanna spend is SPD3303X-E

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 06:50:04 pm
content: Quote from: tautech on April 16, 2020, 06:45:27 pmI'm sure. And nothing to do with the fact that you're a Siglent distributor recommending Siglent power supplies...

author: tautech
author_rank: Super Contributor
timestamp: April 16, 2020, 06:55:29 pm
content: Quote from: engrguy42 on April 16, 2020, 06:50:04 pmNothing at all, I've not recommended anything. Only pointed out a locally available choice for consideration.Whereas you have recommended a recipe for disaster !

author: Gyro
author_rank: Super Contributor
timestamp: April 16, 2020, 06:59:54 pm
content: Quote from: engrguy42 on April 16, 2020, 06:42:33 pmNot at all, the OP is asking for PSU suggestions for developing circuits.IMy advice was to prevent him from destroying those circuits with effectively no useable current limiting.ATX PSUs should be reserved for PC mainboards and 3D printers (with appropriate protection).

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 07:16:35 pm
content: Quote from: Gyro on April 16, 2020, 06:59:54 pmYou're aware that the ATX specification requires internal protective circuits ("supervisors") whose job is to shut off the supply when current exceeds the overcurrent protective level (eg, 240watts/wire), as well as other protective measures?And y'know, like fuses are, like, real cheap.

author: Gyro
author_rank: Super Contributor
timestamp: April 16, 2020, 07:26:48 pm
content: Quote from: engrguy42 on April 16, 2020, 07:16:35 pmThank you for making my point for me so eloquentlyI said nouseablecurrent limit. I am perfectly well aware of ATX PSU specs. 240W/wire doesn't count as in any way effective when you're bringing up or working on the average prototype circuit.It's a well known and oft-quoted fact that expensive Semiconductors will invariably lay down their lives to protect cheap fuses (fuses are used to prevent fire).As I say, point made.

author: jemangedeslolos
author_rank: Frequent Contributor
timestamp: April 16, 2020, 07:31:36 pm
content: Hello,Of course, depending on what you are working on, it could be very very useful to have multiple power supplies.There is a Rigol DP832A for sale on this forum :https://www.eevblog.com/forum/buysellwanted/rigol-832a-bench-power-supply/But maybe you can try to find good price on Korad 3005 or similar. I bought 2 of them for 100€ few month ago.I bought them just because it was cheap but I use them a lot because they are simple, no boot time, fast refresh rate.

author: bd139
author_rank: Super Contributor
timestamp: April 16, 2020, 07:34:13 pm
content: The sound of engrguy42's circuits will be "fum" followed by "pop" when the fuse goes.I'd go for second hand HP / Agilent units myself if you're in the US. Plenty around. Well documented. Very reliable and no nasty surprises. I actually prefer the older ones (HP 62xx series) myself. My main power supply is a TTi PL330QMD which may or may not be available in the US.If you have the choice between something cheap and new or cheap and second hand and was formerly really expensive, pick the latter every time when it comes to power supplies.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 07:37:00 pm
content: For some reason people in these forums apparently have absolutely no ability to comprehend that THEIR needs may not in any way reflect the rest of the world's needs.There are those who don't use expensive semiconductors. Yes, it's true. Many people buy a shit-ton of cheap semiconductors for $10 to try stuff out. If it melts, reach in the box and get another. Go no, right? But it's true.And some people actually consider that they can use an inexpensive ATX supply as a simple, additional source of voltage in a crunch, not to deliver spec-shaking accuracy at 30 amps, but merely to get stuff working.Hard to believe, right? But it's true.Not everything has to be max rating, femto-amp accuracy. It depends on the user. Different people have different needs.

author: bd139
author_rank: Super Contributor
timestamp: April 16, 2020, 07:39:37 pm
content: You can actually seriously injure yourself with an ATX supply if you don't know what you're doing. The 3.3V rail on mine can shift 100 amps easily. You do not want that across a wedding ring or somthing trying to fire up a 3.3V Arduino nano on a breadboard. Also don't want metal vapour in your eyes. Your point is quite frankly retarded.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 07:42:18 pm
content: Quote from: bd139 on April 16, 2020, 07:39:37 pmYou can seriously injure yourself with ANYTHING if you don't know what you're doing or aren't paying attention.

author: Gyro
author_rank: Super Contributor
timestamp: April 16, 2020, 07:44:45 pm
content: Quote from: engrguy42 on April 16, 2020, 07:37:00 pmIf you're going to start arguing on this forum that an ATX PSU is the correct way to bring up a prototype circuit, then you're going to fall on your ass. As BD139 points out, the available currents can be hazardous.Your lack of understanding of how to prototype circuits is disturbing. Decent current limit is essential.

author: bd139
author_rank: Super Contributor
timestamp: April 16, 2020, 07:45:38 pm
content: Some ATX fun... this one made me snigger a bit to be frank. Just to illustrate.https://www.reddit.com/r/WatchPeopleDieInside/comments/g0420s/pc_build_does_not_go_as_planned/

author: bd139
author_rank: Super Contributor
timestamp: April 16, 2020, 07:47:31 pm
content: Quote from: engrguy42 on April 16, 2020, 07:42:18 pmYou don't and you're not giving good advice to people.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 08:07:03 pm
content: Quote from: bd139 on April 16, 2020, 07:47:31 pmFine. I give up. You're right, I'm wrong. Feel better?But speaking of knowing how to breadboard prototypes, it sounds like you had an experience where you tried an ATX power supply and maybe got your wedding ring across it and it shifted to 100 amps?? Sounds a bit surprising, since I've actually tested and overloaded mine and it shut down immediately below its 16A rating, but anyway...Just a thought...maybe in the future don't rely upon ANY power supply to have it's internals working when you need them to. Anything can fail at any time, especially when you're wiring stuff up on a prototype and might do a miswire. I tend to use fuses just in case. Y'know, can't hurt to have lots of fuses lying around. Not for my components, which I don't care about, but for me.

author: jemangedeslolos
author_rank: Frequent Contributor
timestamp: April 16, 2020, 08:11:30 pm
content: Quote from: engrguy42 on April 16, 2020, 08:07:03 pmHe want a lab grade power supply and has enough money for a decent one.Why all of this?

author: bd139
author_rank: Super Contributor
timestamp: April 16, 2020, 08:14:14 pm
content: Quote from: engrguy42 on April 16, 2020, 08:07:03 pmI have never done it because I am capable of doing a risk assessment and eliminating the stupid before I do it.That wasyourpower supply. 16A is still plenty enough to cause burns.Fuses take time to blow. A 10A fuse can hold 15A for a few seconds quite easily. It can hold 30A for a second and 100A for a few milliseconds. Thats enough to cause you trouble and also why you need a dynamic feedback network for current control in your circuit. You need that current limit to kick in right where you want it with no overshoot, otherwise you'll be in the hospital with bits of MOSFET being picked out of your eyes.As for power supplies going wrong you're right. Which is why you minimise the risk by trading your crappy ATX in for a decent quality bench supply. All ATX supplies are unconditionally "volume products" and are built to a price point. Server modular supplies not so much but those are even more dangerous.

author: nctnico
author_rank: Super Contributor
timestamp: April 16, 2020, 08:24:56 pm
content: Quote from: engrguy42 on April 16, 2020, 06:50:04 pmTautech is right. PC style power supplies suck. They are inprecise, noisy (electrically), usually need a minimum load, can pump a massive amount of power into a circuit (enought to make it blow up in your face) and tweaking them is not a really good idea. And if you need a permanent PSU for a project a switching Meanwell PSU which fits the job is likely cheaper.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 08:44:25 pm
content: A little data that might interest some...Now I get that ATX power supplies "suck", and you may be right. But I did do some tests a while back on a decent Dell 650watt power supply. And I was curious if the supervisor circuits actually work when they're supposed to.This particular test was a 12V rail, rated at 16A (as I recall). What I did is use a big honkin' (and inaccurate) rheostat to adjust the load, and manually cranked down the resistance below 1 ohm to see if the overcurrent function shut down the PS before 16A.Now this is in no way accurate, nor does it reflect what might have happened in the final seconds or milliseconds just before the supervisor shut it down, but it appears it did its job and shut down around 12A. Of course it could have jumped up to 1,000 amps just prior to that, but anyway...I forget what the sample rate was, etc.So I think that the old saying "Don't buy junk" applies with ATX power supplies. If you buy a decent, name brand ATX supply, it should do what it says, and provide fairly noiseless, regulated power with all the PFC crap, OV and OC protection, etc.Of course that might not be enough for some, but hey, whatever worksEDIT:FWIW, the sample rate on that chart was every 10 mSec, for 26 seconds total. So if it had seen a big spike within 10mSec it might have missed it, otherwise....

author: Gyro
author_rank: Super Contributor
timestamp: April 16, 2020, 09:11:00 pm
content: I've never doubted for one second that the overcurrent protection of an ATX supply works (as spec) - it has to, it would just go bang otherwise. It's protecting itself.The whole point that youkeepmissing is that it is not adjustable down to a level that is suitable for protecting the average prototype circuit during debug. The other problem that you have omitted is that it is aShutdownmechanism, not a constant current limit (or even foldback) which makes it useless for tracing a fault.Edit: Grammar corrected.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 09:14:06 pm
content: Quote from: Gyro on April 16, 2020, 09:11:00 pmI agree it doesn't have constant current. I mentioned that in my second post. It has limitations. But those limitations might not be as important to everyone as they are to you.

author: bd139
author_rank: Super Contributor
timestamp: April 16, 2020, 09:24:10 pm
content: The limitation was set within the range of the HPAK E3630 which is at least an order of magnitude less grunty and has a hard current limit and fold back.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 16, 2020, 09:37:40 pm
content: Quote from: bd139 on April 16, 2020, 09:24:10 pmI *believe* the PS I was referencing has three easily accessible reference pots that can be used to adjust protective levels if desired. I've never tried it (they have goop all over them), but something to consider for those who want lower protective levels.Of course that's not in the same league as a high end power supply, but anyway...

author: J-R
author_rank: Super Contributor
timestamp: April 16, 2020, 09:38:36 pm
content: There are plenty of dirt cheap variable DC-DC converters around if you really wanted to build something. Replace the tiny pots with bigger ones with knobs and add those equally cheap LED displays and for probably $10-$20 in parts you could have something stuffed into an old ATX supply. They're actually kind of a fun project assuming you have a grasp of basic concepts. You can also use a laptop power supply. Many people have done this, myself included.BUT, I feel this is really more mad scientist than professional electronics tech.For the OP, I would suggest getting a bench supply with a computer interface. It really opens up the possibilities. Also the ability to either float or ground the output could be handy.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 17, 2020, 11:19:44 am
content: Quote from: J-R on April 16, 2020, 09:38:36 pmI agree 100%. I love those cheap DC-DC converters where you can use a simple plug pack and just tweak a pot to get whatever output you want. In fact I just rebuilt an LED bench light using one.I think one of the benefits of the ATX supplies, for those who might need it, is high(er) current capabilities. You can get an inexpensive, ready-to-go power supply that can handle, say, 600-800 watts or more on multiple rails. Which means you can have 3/5/12 volt sources that can handle like 10-20 amps simultaneously.There are many solutions out there. Different solutions for different needs. I just encourage folks to not make up their minds about stuff and totally dismiss it solely because it might not meet THEIR particular needs. Or maybe it actually does meet some of their needs, but they just don't know enough about it because they've already dismissed it as "it sucks".

author: rvalente
author_rank: Frequent Contributor
timestamp: April 17, 2020, 11:31:46 am
content: Why not the RIDEN power supply? Seems pretty ok for the money?Dirty Cheap: DPS module + laptopto power supply, good for up to 60W!https://www.aliexpress.com/item/4000282551930.html?spm=2114.12010612.8148356.2.18e22f3fiWTTIOhttps://www.aliexpress.com/item/1000004290003.html?spm=a2g0o.detail.1000023.23.49797ed8VPtwxj

author: Gyro
author_rank: Super Contributor
timestamp: April 17, 2020, 12:02:46 pm
content: Err, I think, before the thread degraded into noise, that the OP was looking for a 2-3 channel Linear supply, for which he has the budget.Quote from: 5370H55V on April 16, 2020, 06:23:25 pm

author: Gandalf_Sr
author_rank: Super Contributor
timestamp: April 17, 2020, 12:36:06 pm
content: Quote from: engrguy42 on April 16, 2020, 06:50:04 pmI'm shocked, SHOCKED! that Tautech is suggesting a Siglent power supply

author: jemangedeslolos
author_rank: Frequent Contributor
timestamp: April 17, 2020, 12:43:43 pm
content: Quote from: Gandalf_Sr on April 17, 2020, 12:36:06 pmAnd ntnico agrees with him without speaking about GWinstek.Be careful with your second screen and your scope, there will be a thunderstorm.

author: Gyro
author_rank: Super Contributor
timestamp: April 17, 2020, 12:44:35 pm
content: Well that attempt to get the thread back on track worked well didn't it!(In response to Gandalf_Sr's post)

author: nctnico
author_rank: Super Contributor
timestamp: April 17, 2020, 12:49:11 pm
content: Quote from: rvalente on April 17, 2020, 11:31:46 amThe costs add up quickly. These cheap DC-DC modules are very nice to build a PSU which can deliver a lot of power for little money but it still is a switching PSU which is not very useful when working on analog circuits. From experience I can tell you the noise from the DC-DC can easely swamp the signal you are looking at on an oscilloscope. Therefore I highly recommend to get a linear PSU.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 17, 2020, 12:50:52 pm
content: Quote from: Gyro on April 17, 2020, 12:44:35 pmWhat you consider "noise" and getting "off track", others might consider as a learning opportunity. Y'know, discussions of related technical stuff, including people actually providing test data, that maybe those who aren't so full of themselves might learn from.

author: Gyro
author_rank: Super Contributor
timestamp: April 17, 2020, 12:55:35 pm
content: I am far more interested in the OP getting the answer he was seeking, rather than any ATX related noise that you wish to introduce - you can quite easily start your own thread for that!Maybe you're too "full of yourself" to see that!It looks as if he's given up on a sensible answer anyway.

author: nctnico
author_rank: Super Contributor
timestamp: April 17, 2020, 12:56:57 pm
content: Quote from: engrguy42 on April 17, 2020, 12:50:52 pmThe only things you have shown are: 1) that you know absolutely nothing about the inner workings of a PC power supply 2) don't look at the OP's requirements. The OP is looking for a variable power supply with 2 (or more) independent outputs. A PC power supply can't do that.

author: engrguy42
author_rank: Frequent Contributor
timestamp: April 17, 2020, 01:02:22 pm
content: If you actually read the thread I was the first to tell him an ATX would NOT meet his needs.

author: rvalente
author_rank: Frequent Contributor
timestamp: April 17, 2020, 01:14:52 pm
content: Quote from: nctnico on April 17, 2020, 12:49:11 pmI agree and believe in you but, the user did not mentioned he will be using the supply with analog, actually his specifications where next to none, only "good and 250 bucks"...

author: Gandalf_Sr
author_rank: Super Contributor
timestamp: April 17, 2020, 01:26:44 pm
content: What about the PSU that the OP suggested, the HP/Agilent E3630A which can be bought on eBay for $150? It's fairly compact, presumably meets the OP's needs in terms of V/A, and is probably awesome quality both build and output-wise.The biggest drawback I can see to that it you can only see one output at a time.

author: nctnico
author_rank: Super Contributor
timestamp: April 17, 2020, 01:28:18 pm
content: Quote from: Gandalf_Sr on April 17, 2020, 01:26:44 pmIt doesn't have adjustable current limit. I always set the current limit to what the circuit needs to operate. In case of problems the amount of power pushed into the circuit is limited. In the end more energy (power) equates to a larger amount of damage possible (including components exploding violently).

author: rvalente
author_rank: Frequent Contributor
timestamp: April 17, 2020, 01:34:49 pm
content: Tektronix PS280LinearCheap (as low as $130 on ebay)Easy to fixDual outputs, with tracking and current limiting5V outputI believe is a rebranded GW Instek GPC-3020D, you can search for that as well.with you bugdget you can get two of it or save to get a nice multimeter or whatever

author: Gandalf_Sr
author_rank: Super Contributor
timestamp: April 17, 2020, 01:50:13 pm
content: Quote from: nctnico on April 17, 2020, 01:28:18 pmI agree, if it has no adjustable current limit, it's a non-starter. I have the bigger HP/Agilent 6623A which is a triple output and would be in-budget for the OP. Personally I'd prefer to go up to something like a DP832 but that's way over budget.There are the linear multiple power supplies that can be found on Amazonlike this one.

author: rsjsouza
author_rank: Super Contributor
timestamp: April 17, 2020, 03:55:14 pm
content: @5370H55V, if you search eBay for "power supply dual" you will find a world of variants.In your price range and with some decent user interface you have a Tektronix PS2521GeBay auction: #293375855471, the aforementioned PS280eBay auction: #163724264258or, for a larger footprint, a HP 6625AeBay auction: #301312573316.

author: 5370H55V
author_rank: Contributor
timestamp: April 17, 2020, 06:14:10 pm
content: Thanks for all the replies so far. There have been several good suggestions and the Tektronix PS280 seems to be a good choice within my budget. I've also asked around and might be able to get an Agilent E3631A locally at near the top of my price range. How is it compared to the PS280, and would that be a good buy?

author: bd139
author_rank: Super Contributor
timestamp: April 17, 2020, 06:19:38 pm
content: E3631A is very nice if the display is good (they wear out)

author: Gandalf_Sr
author_rank: Super Contributor
timestamp: April 17, 2020, 06:27:11 pm
content: Quote from: bd139 on April 17, 2020, 06:19:38 pmThere's one on eBay right now that's at $44 with 2 days to go.https://www.ebay.com/itm/Agilent-E3631A-Triple-Output-DC-Power-Supply-6V-5A-25V/153898980444?hash=item23d518145c:g:W8cAAOSw0BVelzB-

author: nctnico
author_rank: Super Contributor
timestamp: April 17, 2020, 06:42:06 pm
content: Quote from: Gandalf_Sr on April 17, 2020, 06:27:11 pmBut that is likely to sell for $350 or much more. Just see the completed listings. Crazy money for such an old power supply.

author: nctnico
author_rank: Super Contributor
timestamp: April 17, 2020, 06:47:42 pm
content: Quote from: 5370H55V on April 17, 2020, 06:14:10 pmThe PS2521G looks like a good deal to me because of the LED display which can't go wrong and 3 truly independent outputs. The only downside could be a loud fan but IIRC the E3631A has a loud fan. I'd take a look at the Tektronix PS2520, PS2520G and PS2521 as well. These form a small family of similar power supplies.

author: rsjsouza
author_rank: Super Contributor
timestamp: April 17, 2020, 07:49:10 pm
content: Quote from: nctnico on April 17, 2020, 06:47:42 pmAgree, the LED has a longer lifetime and it is much easier to replace. Also, the Tek has a nicer panel interface and both have a fan that can be loud depending on the load.I also dislike the HP input mode, where the cursor is, in fact, a digit partially dimmed, but that is a personal taste.

author: nctnico
author_rank: Super Contributor
timestamp: April 17, 2020, 08:36:51 pm
content: Quote from: rsjsouza on April 17, 2020, 07:49:10 pmI didn't look that far on the E3631A but it seems it doesn't have a numeric keypad.Trust me: together with cursor positioning that is going to totally suck. If you buy a digital PSU then get one with a numeric keypad.

author: rvalente
author_rank: Frequent Contributor
timestamp: April 17, 2020, 10:00:07 pm
content: Quote from: nctnico on April 17, 2020, 08:36:51 pmThem its point up to the HP 63xx series, its a beast, LCD panel that very unlikely will to go bad and keypad

author: JUNCE LEE
author_rank: Newbie
timestamp: April 18, 2020, 05:05:15 am
content: If you consider the issue of cost, you can buy a DC-DC conversion module, many of which have used color screen display and knob operation, and are equipped with second-hand AC-DC switching power supply. DIY self-assembly, both powerful and cheap ;

author: electricMN
author_rank: Regular Contributor
timestamp: April 18, 2020, 04:22:41 pm
content: I can suggest this Korad KA3305P programmable linear power supply. I've had one for three years now and it hasn't missed a beat.https://www.amazon.com/KORAD-KA3305P-Programmable-Precision-Adjustable/dp/B012LMOI84

author: Gandalf_Sr
author_rank: Super Contributor
timestamp: April 18, 2020, 06:12:34 pm
content: Quote from: electricMN on April 18, 2020, 04:22:41 pmActually, I have one of those, the UI is a bit weird (unless they changed it) but it does the job.

author: rvalente
author_rank: Frequent Contributor
timestamp: April 20, 2020, 09:44:03 pm
content: Quote from: electricMN on April 18, 2020, 04:22:41 pmCan you get service manuals for korad products?

author: electricMN
author_rank: Regular Contributor
timestamp: April 20, 2020, 11:56:02 pm
content: Quote from: rvalente on April 20, 2020, 09:44:03 pmNot sure, I've never checked. I do have a calibration process though.

author: bluey
author_rank: Regular Contributor
timestamp: May 09, 2020, 11:29:07 am
content: The old HP ones look very nice - same design as the E3630A, just different label.

author: karamba
author_rank: Contributor
timestamp: May 09, 2020, 04:31:33 pm
content: Quote from: engrguy42 on April 16, 2020, 07:16:35 pmWhen you start making stuff you will discover very fast that 240W can melt almost anything. Overcurrent protection is for the power consumer not the supply.