Benchtop power supply

Hiya guys. I’m looking to purchase or build my first variable benchtop power supply.

I could make from an old ATX PSU, but I’m also good with spending a little money to have variable voltage.

  • I was thinking of picking up the controller, case and power supply from this link (60V, 18A, comes to $160 when assembled)
  • or, I could just buy a beginner supply from Amazon (link with examples)

What do you think of going in one of these directions?

For me? I’d buy an old lab grade one instead. I have an HP6034a that I got really cheap used, and I keep coming back to using it even when I have other “better” supplies because it’s so rock solid.

I gotta agree with @malcolmputer. This was one of my first lab purchases and now I have like 4 of them from the same series: https://www.ebay.com/itm/HP-6034A-SYSTEM-POWER-SUPPLY-0-60V-0-10A-200W/173544423740?epid=1308739575&hash=item28680dc13c:g:sxQAAOSwcMhboo2~

I paid about $100 each, give or take.

But I also can’t really argue with getting one of those switching supplies you linked on Amazon. We use those at DMS and they’re great.

I’ve used my own and I’ve used the ones at DMS and I don’t really have much of a preference. I don’t trust the switching units as much as I trust my linear HP units, but that’s an entirely unscientific and largelely useless statement.

I have this intuition that your this link option might end up being my favorite, but I haven’t tried it and that makes it hard to comment on.

This is a switching power supply I bought on Amazon, primarily to do plating which is why I opted for the 10A version for larger pieces. Has worked fine for me on all uses so far, $72. Its nice and light weight.
Yescom 110V AC 30V 10A DC Power Supply Precision Variable Digital Adjustable w Clip Cable

@benemorius As I’ve watched a few more videos, I’m now looking to see if I can find the same pieces from the ALi Expterss link, but with a multi-output option. It looks like all the modern lab boxes are three basic pieces - a Controller front, a case, and a power supply that can be various specs depending on how much money you want to spend.

The HPs that you and @malcolmputer are showing up on ebay for $250 - $350 once you include shipping and taxes. I’, leaning towards the BYO using the Ali Express parts, or just convert one of my old ATX supplies. In other words, go cheap for now, or maximize my spend capping at no more than $200

What I use daily. Don’t remember what it cost (I put it on my company card, lol) but it’s overkill for hobby work, though they have cheaper models. Couldn’t be happier. If they have a cheap 2-output version I wouldn’t hesitate to buy it.

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Alright, look for a lower end high-end power supply used for cheap then. How about something like this:

https://www.ebay.com/itm/Hewlett-Packard-6632B-0-20V-0-5A-System-DC-Power-Supply-Single-Output-HP-IB

My opinion on test equipment is buy it right the first time.

@malcomputer I agree, and it is also my philosophy…but I only have so much capital. For only 20V 5A, those still almost cost as much as the first one you suggested…I would spend the extra for the one you suggested, or build out a kit version instead…

@mdredmond That is more along the lines as what I’d like…if I come across similar under $200, I might snatch it up.

At the end of the day, I would be using it for the occasional small electronics item, or an IP camera…and now that @Photomancer reminded me of plating…I guess I need to take that into consideration as well…

Don’t forget electric fence charging, stick welding, Kirlian photography, hydrogen generation, and black op interrogation just to name a few. We are after all Makers!

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I was in the same place you are a few years ago Clayton. I wanted to build or buy a decent bench PSU. I ended up building one with stuff I had around with the help of a friend who’s an EE. But I then bought a KORAD KA3005D.

There are many reviews for it on YT. It’s been around for quite some time so it’s had a lot of longevity. I think you can pick one up for sub $120 if you don’t mind waiting for shipping…

One of the features I like best about it is the output switch control (which I would recommend with any unit if you buy. This lets you keep the power on to the PSU itself but to turn the circuit on/off with an electronic switch. It’s also easy to dial in the voltage/current you want before powering the circuit. Very helpful. Plus over current and voltage protection… I use it for many things including charging 18650 batteries and any/all my arduino projects where i’m curious to check current consumption.

Good luck.

PS: If you watch the EEVblog review (both), be sure to notice the update he make after the vid regarding Korad’s recognition of the problem he noticed. And there was a great follow-up video as well showing the corrected results. And this was ~9 years back. Like I said, it’s been around a while, which I take as a good sign.

image

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@Photomancer stick welding with a desktop 30V or 60V 5a power supply. Really? Or are you pulling my leg?

@Paul_Morley I found his channel yesterday. He reviewed the previous version of the item I linked in Ali Express.

@benemorius & @malcolmputer, I just noticed the HP devices you mentioned do not have probe sockets or posts on the front…do you have probes permanently attached to the rear of the power supply?

Some do some don’t the “system power supply” only has contacts on the back, but I’ve just run long leads to the most common connector I use in the lab. The cool thing is, most of the supplies support “remote sense” or 4 wire sense, so I actually have separate sense leads all the way to my connector, which means voltage drop is cal’d out.

I’m the worst person to ask, built a +/- 15V, 5V triple in 1980 for testing, it still works, and I still use it.

They are making amazing switching chips now, for nothing. There are inductors, caps, and resistors to program, in the e-Lab; all you really have to do is apply the App Notes. Learning by doing is it’s own reward.

It all depends upon your budget and desire. Realistically, one could easily use a PC power supply from an old box for zero cost, but if you need -V for analog amps, this won’t do.

Here is a hint: https://www.ti.com/lit/sg/slvt145r/slvt145r.pdf?ts=1602561553406&ref_url=https%3A%2F%2Fwww.google.com%2F

@Russell_Crow I have no idea what negative voltage is used for…I guess I need to add that to my google list…

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Analog circuits for the most part. Op Amps, discrete amplifiers, etc all love to have inputs and outputs centered around 0v.

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Yes, analog amps, audio and instrumentation, and analog computing (don’t laugh, it’s still faster).

And thanks to @michaelb, -HV will be used in Deuterium Fusion.

Thanks Michael!

If you haven’t purchased one… I have this triple output power supply for sale.

Channel 1: 0-18v at 0-5A
Channel 1: 0-18v at 0-5A
Channel 3: 5v at 3A fixed

You can run Channel 1 and Channel 2 independent, in parallel for extra current, or in series for extra voltage. They also have isolated grounds on channel 1 and 2 so you can have +/- voltages out.

$75 <SOLD on Facebook 11/3. No longer available.>

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