Is there such a thing as a Lab Power Supply with a decent UI?

[Dubbie]

I've been looking around at another lab power supply and man am I ever unimpressed with the UI on all that I have seen so far.
I'd like 2 or 3 outputs. Power between 50-100W

Currently I have a Rigol DP832. I have pretty much no complaints with it's function and features. However the UI, both physical and screen is awful.
The setpoints for V and I are teeny tiny on screen with unlabeled buttons to set them.


I have looked at a few options out there.
The Siglent has a very nice screen with large readout. However the screen doesn't display the setpoints all the time which I don't like. The other problem with it, is that the banana jacks seem to be pretty janky with non standard spacing and out of tolerance bore.  I'm also a little leery of the slider to select the CH3 voltage. Also the screen turns off after a while. No thanks.

The R&S looks very nice, but very expensive. It has some great sequencing and ramp features that the others don't have
However the screen once again doesn't show all the data all the time. The dedicated LABELED buttons to set V and I are very nice.

The keysight power supplies look like they last got an update when McGuyver was on its first run.

the GW Instek PPH-1503D looks ok. I like the sense terminal on the front. Once again, the setpoints are teeny tiny. Weirdly, CH-2 only seems to be on the rear.

Things I'd like:
As large as possible display of V, I, W, Vset, Iset for each channel
Dedicated labeled buttons to set both V and I
knob with left and right cursor arrow buttons to set the values. Numpad optional.
Sense on front would be nice.
Separate on/off switch for each channel.
It would be nice if it accepted shrouded bananas
Linear of course.

If anyone has any ideas I'm all ears!
I really think there is a gap in the market for a power supply with a sane UI

[tautech]

Rhys, I have SPD3303X-E on hand, come and have a play with one, of course with no obligation to buy.

I too was concerned about the reportedly loose banana sockets, they are a bit until a plug is fully inserted.

If you want I can check specific things in the UI.

[Dubbie]

Thanks for the offer Tautech. I'll see how I get on. I might just have to come and take a look at some point.

[Assafl]

I guess the industry is at the stage of the game where the display is still a replacement for 7-segment or alphanumeric LEDs and application specific LCD displays (which were replacements for analog meters).

In the future, UI will be skin-able. So that if you want a prominent Watts vs. Volts vs Set-Volt, you could assign real estate to it on the display. A good example for skin-able 'real estate' in embedded software is the Garmin Sports and Bicycle GPS - where you can decide to have a large BPM, small mileage, and a mid size elevation graph.

I don't think it is a question of "if" it will happen. I think it is a question of "when".

[Dubbie]

I think you might be right.
You have no idea how tempting it is for me to build my own, but I have no time nor space for a project of that size right now!

[james_s]

I'm a big fan of good old fashioned analog knobs. I like analog meters too when they're good ones, but good quality analog meters are hard to find anymore. Sure, digital is more precise, but how precisely do you really need to set a power supply generally? Big bright LED displays are nice too. I'm not a fan of the fancy color TFT displays, as you've noted, the UI usually sucks, they're form over function, meant to look fancy and modern at the expense of usability. Good linear bench power supplies have not really changed much in 40 years. For some uses fancy programmable features are nice but I rarely find a need for anything like that.

[H.O]

Hi,
I agree that the setpoint display on the DP832 is small but I don't quite understand what you mean/want with "dedicated buttons". I find it rather intuitive to set both the voltage and current limit using the numeric keys. To set the voltage of channel 2 to 3.3V, 0.5A current limit press [2] enter 3.3V, 0.5A, done. On the R&S it looks like you need to muck around with the SHIFT key to access the numeric keys but I've never actually used one so I don't know.

I think I would have preferred a "normal" numeric keypad over the old telephone style they went for (and got a lot of heat for) but I don't think it's that bad really.

Anyway, don't want to start yet another my unit is better than yours (besides we both have the same unit), I'm just curious what it is you find unintuitive with the way you set U & I on it.

EDIT: I guess one COULD create an external control box for it (or any programmable PSU) with whatever UI features needed if you really wanted. Of course, if a unit with those features already exists then what's the point...

[Messtechniker]

Modding in a VGA output would certainly make for a good project. 
Time permitting of course.

[Dubbie]

I was actually mistaken, the R&S does not have dedicated buttons for setting V and I. The rigol does have them in a way, but you have to peer at the screen to double check which one it is, because they are multi use buttons. I think the rigol is kinda the best of a bad bunch. It could just have been a lot better! I thought someone might know of the perfect unit out there somewhere [emoji16]


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[julian1]

Linear of course.

I love the simple design and form of the R&S, so I went looked for a teardown. It's actually a switcher,

With  the unit open we can see on the upper level, a panel holding a fan and a third-party, industry standard, open-frame 200-watt AC/DC, switched-mode supply unit. This unit supplies 48 V DC to the lower PCB where it divides into three micro controller (Microchip dsPIC DSC’s) controlled DC/DC switching regulators for outputs to the front and rear panels.

pdf,
https://www.elektormagazine.com/files/attachment/48

[Dubbie]

@ Julian

Huh! Was not expecting that.

Although I did pause on the brochure where it mentioned something about efficiency and thought "wonder what they are on about there" now it makes perfect sense.


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[djnz]

I am not sure if I like fancy displays on power supplies.

The power producing portion of a good power supply will last decades, perhaps much longer than the manufacturing lifecycle of the sku. The display could (will?) fail earlier, and with custom fancy displays, finding replacements becomes hard if the power supply is out of production. I am not sure the utility of custom shiny LCDs outweighs this pretty big con.

[H.O]

The rigol does have them in a way, but you have to peer at the screen to double check which one it is, because they are multi use buttons.

I still don't understand what you mean....
Press the button for the channel you want to set, enter 12.5V, 1.25A and you're done. How can it be made more intuitive?

Do you mean you want dedicated buttons that "connects" the rotary knob to a specific setting? If so, have you tried simply pressing V or A and then rotating the knob (I haven't so I don't know if it works).

[capt bullshot]

The best bench power supply UI is (imho):

2 LED displays (actual U / I ) per main channel
2 knobs (10 turns pot) for set U / set I per channel (set I may be a single turn pot)
a simple pushbutton to read set U / I per channel

2 main channels 0.., 30 to 50V and 0 ... 1 to 5 Amps (maybe more than one unit to fulfill all useful ranges)
the typical 5 Volts aux channel isn't neccessary imho

+ output connector right or above - output connector (this is very important to me)

You will find some older types from Toellner, Heinzinger, Delta elektronika wich fullfill most of the requirements. I don't like the HP / Agilent style (output connectors swapped)

[john61ct]

Anyone know of Linux- Raspberry Pi-Arduino controlled PSU hardware?

[Awesome14]

I use the Soresen XTS quad. It's four discrete supplies in one chassis. The individual supplies are available in 7.5V 8A, 15V 4A, 30V 2A, 60V 1A, 120V 0.5A. Any combination of those five is available in the quad units. Each unit has a large LED readout for V and I to 3 digits.

Accuracy is <= 1mV, and I've tested it. Each unit can be configured with GPIB, serial, and/or Ethernet. Each discrete unit has front tellurium-copper bananas, including 'sense', and the rear has output and sense screw terminals.

There is no indication for 'set' values, except the display. You just fiddle with the knobs until it's set the way you want. The V pot is 10-turn and the I is 1-turn. The supplies are linear, fanless, and programmable via PC connection.

I have (2) XTS-15-4 quad supplies.

You can also put the individual supplies in serial for combined voltage, or parallel  for combined current. The unit I'm running has been up for at least 2 years, 24/7. These machines have a US Military specification.

New they are prohibitively expensive: 2,800.00USD range! But on eBay they go for ~300.00USD for the lower voltages, up to ~1,000.00USD for the higher ones. The discrete units are also sold individually.

I purchased a 60V 1A single for my Dad for his birthday. These supplies are made for industrial and military use. They all bear the name Sorensen, but have been manufactured by several companies, including Raytheon, Xantrex, and Ametek.

The Raytheon are the oldest. The ones I have are Xantrex. The newest are Ametek. For linear supplies they're pretty efficient, but there's only so far you can go with that. And <=1mV is not spectacular, but then you're getting into voltage references.

I used to have PSUs all over the place. After I found these I got rid of most of them. And, if your looking for a great UI for any instrument, connecting it to a PC is going to give the BEST UI. However, software can be pricey!

[iainwhite]

Anyone know of Linux- Raspberry Pi-Arduino controlled PSU hardware?

Prasimix's open source power supply ->  https://www.eevblog.com/forum/projects/diy-programmable-dual-channel-bench-psu-0-50v3a/
(uses an Arduino )

[tautech]

Thanks for the offer Tautech. I'll see how I get on. I might just have to come and take a look at some point.

There's been changes to the SDP3033X series UI....pic from a brand new unit showing the default display. (Websites need updating. Grrrr)

[Gyro]

I have to agree with what appears to be the growing majority trend... Analogue knobs.

I see no point in keypads, fancy TFT displays and encoders (that Rigol (?) one that appears in Dave's videos looks apalling!) Personally I prefer coarse and fine adjustments to multi-turn, just quicker to set (but much easier to disturb too). Simultaneous Voltage and Current displays and current limit indication. I can't see any point in displaying Watts either, it just distracts from the important information.

For specialist needs you might want GPIB, digital setup etc. but not for a general Lab supply.

[Dubbie]

Tautech,

Thats looking much better!
Can you also confirm that the screen stays on?
Also that the binding posts are better quality?

[tautech]

Tautech,

Thats looking much better!
Can you also confirm that the screen stays on?
Also that the binding posts are better quality?

Yes the Binding posts have been changed I have been told.
I never had any of the early units so I have no comparison with the later units but I have never had any comments from customers that they were too loose. The first portion of insertion appears very loose but I can assure you the last portion to push it home is NOT, there's no way in hell a lead would ever fall out or become disconnected in normal use without a darn good yank.
Siglent America in a post I found earlier confirmed the binding posts have been upgraded.

The screensaver is still the same BUT is under some discussion behind the scenes. 
We're asking for it to be dropped but as there's not a Menu structure in these units ATM so to provide for screensaver off/on selectability it's unsure how it will be addressed. Dropped I hope.

See Reply #35

[james_s]

Why would someone put a screensaver on a LCD screen? Screensavers are to prevent phosphor burn on CRT displays, there is no reason to have one on LCD, there is no phosphor to burn.

[JonM]

There is the EEZ H24005: Open Source Bench Power Supply project currently on CrowdSupply. If you don't like the UI you can change it. I'm in for one full kit myself.

https://www.crowdsupply.com/envox/eez-h24005/updates/production-planning-and-nearing-third-stretch-goal

https://www.eevblog.com/forum/crowd-funded-projects/preparing-eez-h24005-for-crowdfunding/75/

[kcbrown]

Why would someone put a screensaver on a LCD screen? Screensavers are to prevent phosphor burn on CRT displays, there is no reason to have one on LCD, there is no phosphor to burn.

A "screensaver" that merely displays some sort of pattern or something is worthless on an LCD.

But a screensaver that turns off the backlight is an entirely different thing altogether, since LEDs have a limited brightness half-life (or something approximating one).  Of course, whether the LCD lasts long enough for the LED lifetime to matter is a different question ...

[Assafl]

A decent encoder is cheaper than a decent multi-turn.
A decent keyboard is cheaper than two decent potentiometers.
An LCD (or even a TFT display - and in the near future - OLED displays) are cheaper than an LED display with drivers and large PCBs required. LEDs are cheaper than decent d'Arsonval movements.

The BOM is substantially cheaper to have the "digital" controls - which are okay - but lack the "tactile" feedback of real analog controls and the confidence inspiring analog displays.

But we do get Watt readings and other goodies that the analog stuff sucks at....