Author Topic: EEVblog #509 - Rigol 832 Lab Power Supply  (Read 94340 times)

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Online EEVblog

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #175 on: August 21, 2013, 12:26:48 pm »
*) The confusion this can create among beginners, as they may struggle to understand which features are or are not important, and what gear they may (not) need when getting started.

Any advanced test instrument will have that problem, nothing unique to Rigol.

Quote
*) Obscuring through careful marketing and other means exactly which - potentially expensive to implement - core parameters are considered important for a given type of gear. Which would you rather want: A gazillion extra GB of sample point storage in a DSO, or 300 MHz of extra bandwidth for a total of 500? Remote voltage sense in a high current PSU, or a beautiful LCD color display?

Nothing unique to Rigol here, everyone does it. Take that 10 count error in the Fluke for example, try finding it in the manual, it's not obvious.
Not on in test gear either, every chip maker does it.
As long as nothing is deliberately missing from the datasheet, what's the problem?

Quote
*) The potential risk of obfuscation of the important parameters and features these bells and whistles may create, when the community talk about a given piece of equipment. It is easy for everybody to talk about the front panel layout of the DP832. It may be a bit more difficult and time consuming to explain to a beginner, why I have chosen to pay good money for an E3644A for my home lab.

Once again, what is unique to Rigol here?
The same could be said about any of Agilent's fancy new gear.
The community will talk about what they want to talk about. If you see the case as you describe then why not start thread, do a blog post or video etc on the topic?
You can't expect threads on anything to go the way you want them to go, you can only attempt to drive them there yourself.
 

Offline FrankBuss

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #176 on: August 21, 2013, 02:27:26 pm »
Just one hint from my side to people currently in the market for a new PSU: don't overlook the Siglent SPD3303 series. There are some pros as well as some cons comparing it to the Rigol, chances are you'll like it better.
Looks nice: Siglent SPD3303D/S, I've just ordered one. Costs EUR 279 at eBay here in Germany (free shipping), so a bit less expensive than the Rigol. I'll report back when I have it how it works.

Too bad that the manufacturers don't provide the schematics anymore. Maybe the power-up glitch could be easily fixed with just a pulldown resistor at the gate of some FET. I guess it can't be fixed by a firmware update, because looks like it was right after power-up when the operating system might still booting (looks like some Windows system with the c:\).
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Offline Zbig

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #177 on: August 21, 2013, 02:38:29 pm »
Looks nice: Siglent SPD3303D/S, I've just ordered one. Costs EUR 279 at eBay here in Germany (free shipping), so a bit less expensive than the Rigol. I'll report back when I have it how it works.

Too bad that the manufacturers don't provide the schematics anymore. Maybe the power-up glitch could be easily fixed with just a pulldown resistor at the gate of some FET. I guess it can't be fixed by a firmware update, because looks like it was right after power-up when the operating system might still booting (looks like some Windows system with the c:\).

And it works nice, too (well, at least for me). As for the power-on ("hard" power-on with a mains switch) glitches, I haven't noticed any on either of the two main outputs, but I did on the CH3. It's differrent kind of glitch, more like a spike and chances are it's because of the mains wiring in my house, i.e. no grounding (yes, I know ;))

As for the "C:" drive, I'm almost certain that's not Windows and they did that just so it looks familiar.
 

Offline TerminalJack505

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #178 on: August 21, 2013, 03:30:52 pm »
Dave, hopefully you will find the time between stuffing envelopes to do a teardown. 

I'd also like to see you do additional testing on the power-on glitch.  Someone earlier in the thread suggested that it might just be EMI so I'm curious to see how you test to confirm that that's the case or not.
 

Offline FrankBuss

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #179 on: August 21, 2013, 04:01:48 pm »
The 1.5V for 250ms on channel 1 with no load is not an EMI effect, but should be no problem if you don't power very low voltage, low power things with it. The 4V on channel 2 for 10us might be more serious, because it is still there with the 10 ohm load. But 10us is short, maybe this could be some EMI effect? :-// But most parts would survive it. For many 3.3V microcontrollers, 4V is not much higher than the maximum rating.

Dave, maybe you can test it again with some real-world applications, like a 10uF capacitive load in parallel to a resistive load?
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Offline KedasProbe

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #180 on: August 21, 2013, 04:34:02 pm »
Anyone daring to test the power on current spike with shorted output?
Not everything that counts can be measured. Not everything that can be measured counts.
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Offline PuterGeek

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #181 on: August 21, 2013, 08:29:13 pm »
Dave,

Not that you need my advice or permission...

Make whatever videos you want and work on projects that interest you! That is what got you here and why you do it!

Your popularity is entirely because of your knowledge, experience and obvoious excitment!  :clap:

I'm not suggesting you ignore suggestions but temper them by your interest or it won't be the same.

-Joe
 

Offline ElectroIrradiator

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #182 on: August 21, 2013, 09:19:28 pm »
Any advanced test instrument will have that problem, nothing unique to Rigol.
I beg your pardon? Are you saying the Agilent E3631A is about to get an upgrade with more bells and whistles? Well, admittedly it has only been on the market since the nineties, so I guess it is due for an overhaul. Which crucial features do you believe needs to be added, or how should its user interface be changed, compared to the Rigol DP832 ? (Yes, I am aware the E3631A only delivers 1A on the +/-25V rails).

As long as nothing is deliberately missing from the datasheet, what's the problem?
Try having a really, really close look at the detailed specifications for the Agilent DSOX-2022A and the Rigol DS2202. I will admit you may need a good magnifying glass, but it does look to me like there are a few interesting differences, apart from the obvious ones like sample memory depth. I will try to provide more info ASAP, if you are unable to spot any issues.

Once again, what is unique to Rigol here?
The same could be said about any of Agilent's fancy new gear.
The community will talk about what they want to talk about. If you see the case as you describe then why not start thread, do a blog post or video etc on the topic?
You can't expect threads on anything to go the way you want them to go, you can only attempt to drive them there yourself.
Uhm...? ???

*) I said 'Rigol & Co.' Many other manufacturers are guilty of the same issues IMO.
*) Agilent seem to introduce new models, when they have made actual technological advances, like the 1 million waveform updates per second in the 3000X/4000X scopes. Conversely, a good part of their program of linear benchtop lab PSUs hasn't changed in ages, since there is little to innovate here. You can only differentiate yourself in this area on price (lower quality), voltage and current levels for different rails or added features (UI bloat, see previous E3631A vs. DP832 comparison). Well, none of the Agilent PSUs have LXI as far as I know, there is that, of course.
*) I am talking about it. Right now. Not even sure I understand where you think you are going with the last two sentences.
 

Offline Elandril

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #183 on: August 21, 2013, 10:05:08 pm »
I have to say that the mentioned Agilent E3631A is a perfect example for what I call eye-cancer gear. In 2013 offerinbg a product in this price range with such an atrocious display is in my opinion a crime. In the 21st century a good multi-color high-res display and some nice layout & software design is not too much to ask for.

But also the Rigol is in some aspects more of a they-tried-but-failed product in terms of usability: true, the monochrome themes are not so bad really, at least well readable, but what is the point in having a multi-color display, if you just use one color in various brightness? I think these themes should be upgraded with some colors for warnings and and some additional info (e.g. current/voltage limit reached), and in addition they should design some "modern" ui elements that take full usage of state-of-the-art fonts and gui design. Clearly in the sister product DP832A they tried to do that, but ultimately failed, because the three display sections for the outputs are not really have-a-quick-look friendly. And they I don't even want to mention the completely botched numeric keys and rotary knob. Whoever came up with that should be sentenced to having to use such a keypad for the rest of his life.

All in all I think it's very refreshing for the market when new and feature-rich products get released by companies such as Rigol which now clearly have evolved from the entry/hobbyist segment into the (semi-)professional region. Many of the older professional big players have just kind of slept for the last 20/30 years when it comes to product design and usability. Today everything is basically done in software (and this often better than any hardware could ever do), so I think the customers have a right to demand products which utilize their capabilities to the full extend.
 

Offline sync

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #184 on: August 21, 2013, 10:51:36 pm »
I beg your pardon? Are you saying the Agilent E3631A is about to get an upgrade with more bells and whistles? Well, admittedly it has only been on the market since the nineties, so I guess it is due for an overhaul. Which crucial features do you believe needs to be added, or how should its user interface be changed, compared to the Rigol DP832 ?
Displaying the values for all channels at the same time.
 

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #185 on: August 21, 2013, 11:39:47 pm »
I beg your pardon? Are you saying the Agilent E3631A is about to get an upgrade with more bells and whistles? Well, admittedly it has only been on the market since the nineties, so I guess it is due for an overhaul. Which crucial features do you believe needs to be added, or how should its user interface be changed, compared to the Rigol DP832 ?
Displaying the values for all channels at the same time.

Absolutely.
To have such a huge front panel like that on a triple output supply and only display one channels V/A info is just stupid.
 

Offline Electro Fan

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #186 on: August 21, 2013, 11:58:40 pm »
I beg your pardon? Are you saying the Agilent E3631A is about to get an upgrade with more bells and whistles? Well, admittedly it has only been on the market since the nineties, so I guess it is due for an overhaul. Which crucial features do you believe needs to be added, or how should its user interface be changed, compared to the Rigol DP832 ?
Displaying the values for all channels at the same time.

Right, this is what is happening as display technology advances and as software becomes more familiar to both product designers and users.

When you have a one line display with a relatively limited amount of segment-based characters the product designer decides if the user should first see actual volts and actual amps or maybe set volts and set amps, but either way the user can can toggle between actual volts and actual amps to set volts and set amps, etc.  When you get bigger displays you gain enough room for actual volts, actual amps, set volts, and set amps to all be displayed simultaneously.  And that's for channel 1; if you have a 2nd channel maybe you have to hit a button and toggle some more.

As an example of the limitations and trade-offs forced by conventional segment-character displays you get (I realize these are electronic loads vs. a power supply) the BK 8500 vs. the Manyuo 9712.  The BK shows volts and amps on one display, hit toggle and you can see ohms and watts.  On the Maynuo you can see all four (volts, amps, ohms, watts) at the same time - which is nice if you want to watch some of the values drive the other values.

The next step up from adding more segmented characters per line and more lines per display is your basic LCD technology that descends from computer monitors and TVs.  Now you can have bigger displays that present more information and no longer are you limited to alphanumerics and a few special characters.  You can get graphs or potentially pixel-based images of almost of anything.  No doubt, those resistant to change will say "well, I used to use a slide rule and I can do all the calculations in my head even without the slide rule - and anything more than the basics (whatever those familiar values might be) will defocus me from my mission", or something like that.  For those people there could be a user option to display just the basics - whatever those might be.  In a really well designed user interface such preferences (such as just "the basics" or extra large characters for viewing from across the lab, or whatever a user wants - within some reasonable confines) could potentially be designated user by user or lab by lab (if you wanted to standardize in a workgroup.)

We are now crossing over from what Agilent (and others) made so well recognized, understood, respected, and trusted to new ways of displaying information.  Some people will prefer the old way/basics and others will prefer more information rich approaches.

My opinion is that the new technology and the additional information it can surface is potentially very desireable and I predict new user interfaces will evolve and some new version of the new way will become the new norm (even if it takes a few users kicking and screaming with it).  BUT, and this is a big BUT, all of this display and user interface stuff is close to worthless (or worse than worseless) if it isn't backed up by reliable signal acquisition and processing.  The data must be accurate to within published specs so that users can rely on the data acquired and presented whether they get it by visualizing a single monochrome character at a time as it scrolls by like an old stock ticker symbol display or by watching it in 3D color holographics.  AND further, and this is a BIG AND, neither the user interface or the integrity of the signal and the resulting displayed information is of any value if the test equipment doesn't protect the DUT and the user.  The first job of test equipment (used responsibly) is to DO NO HARM. 

So, in ascending order (from #3/third most important to #1/most important), we get:

3. New displays and user interfaces are on the way - we should find a way to embrace and continually improve them.
2. More important than the display/UI (which is very important) is signal aquisition and processing integrity.
1. More important than 1 or 2 is that test equipment should do no harm to a responsible user or the user's DUT.

 
« Last Edit: August 22, 2013, 12:34:04 am by Electro Fan »
 

Offline olsenn

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #187 on: August 22, 2013, 12:06:12 am »
Dave, how are you liking your DP832 so far? Will you be doing a full review and/or teardown anytime soon?
 

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #188 on: August 22, 2013, 12:14:50 am »
We are now crossing over from what Agilent (and others) made so well recognized, understood, respected, and trusted to new ways of displaying information.  Some people will prefer the old way/basics and others will prefer more information rich approaches.

I hold HP/Agilent gear in as much reverence as anyone, but that single channel display was as shitty back then as it is today. There was never any respect for that IMO. It's just the way HP/Agilent did it, and if you wanted HP/Agilent that's what you got.

Quote
So, in ascending order (from #3/third most important to #1/most important), we get:
3. New display and user interfaces are on the way - we should find a way to embrace and continually improve them.
2. More important than the display/UI (which is very imporant) is is signal aquisition and processing integrity.
1. More important than 1 or 2 is that the test equipment should do no harm to a responsible user or the user's DUT.

While they are at, they should maybe think about tightening up that loose +20mV spec on the voltage set. That's worse than Rigols.
After all, what good is that voltage sense input if your spec is 0.6% on a typical 3.3V output.
Oops, just realised the sense input is not available on the base model E3631A
« Last Edit: August 22, 2013, 12:20:30 am by EEVblog »
 

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #189 on: August 22, 2013, 12:21:24 am »
Dave, how are you liking your DP832 so far? Will you be doing a full review and/or teardown anytime soon?

Haven't done anything with it, or anything else, I've been very sick for a week now.
 

Offline Electro Fan

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #190 on: August 22, 2013, 12:28:57 am »
We are now crossing over from what Agilent (and others) made so well recognized, understood, respected, and trusted to new ways of displaying information.  Some people will prefer the old way/basics and others will prefer more information rich approaches.

I hold HP/Agilent gear in as much reverence as anyone, but that single channel display was as shitty back then as it is today. There was never any respect for that IMO. It's just the way HP/Agilent did it, and if you wanted HP/Agilent that's what you got.

Quote
So, in ascending order (from #3/third most important to #1/most important), we get:
3. New display and user interfaces are on the way - we should find a way to embrace and continually improve them.
2. More important than the display/UI (which is very imporant) is is signal aquisition and processing integrity.
1. More important than 1 or 2 is that the test equipment should do no harm to a responsible user or the user's DUT.

While they are at, they should maybe think about tightening up that loose +20mV spec on the voltage set. That's worse than Rigols.

- Some guys might be slightly more brand and model reverent than others  :-DD

- Absolutely, in order to rely on and trust a piece of equipment the salient specs should be readily available (not hidden or made difficult to find); in turn, I think in the future - especially given the Internet and sites and forums such as this - that the occassional (or not so occassional) outlier spec or feature or problem that frustrates users (especially on an otherwise good product) will be surfaced more readily from the user community to the equipment providers and the better equipment providers will find a way to incorporate the feedback into a new release (as either new firmware/software or new hardware)
« Last Edit: August 22, 2013, 12:32:31 am by Electro Fan »
 

Offline Corporate666

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #191 on: August 22, 2013, 04:28:51 am »
I am amazed at how catty and fanboi'ish people get over test gear!

I like all the features Rigol is bringing to the market.  They are raising the game, aren't they?  And forcing the competition to increase value or get pushed aside.  I really like my DP832.  I think it's funny that people complain about the rotary knob and circular arrangement of numbers without having ever having used one (I got used to it quickly and now I like it maybe more than a traditional keypad - it's easier to hover my hand over the knob and make any adjustments I need).  But the same folks who complain that the knob isn't as good as it could be justify other PSU's not even having knobs at all because they aren't gimmicky?

It's a giant pain in the ass to set OCP/OVP or even to set the voltage and current levels on my Agilent or Fluke supplies compared to the Rigol.  I understand that engineers are infinitely picky, but some of the complaints aired seem to me to be akin to bitching about how the traction control in race mode in the new Ferrari 458 doesn't let you slide the ass end of the car enough before it kicks in, as you drive your 1994 Corvette  :-DD

The power spike at turn on *is* a genuine concern and while it won't have any effect on the stuff I do, it shouldn't happen... on the other hand, has anyone checked their 832 to see if it does the same thing?  Do we know something isn't wonky with Dave's unit?  Or maybe his is better than most and others spike to 20V?  Maybe it's not a design fault but something else? 

It's not always the most popular person who gets the job done.
 

Offline Electro Fan

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #192 on: August 22, 2013, 04:50:24 am »
I am amazed at how catty and fanboi'ish people get over test gear!

I like all the features Rigol is bringing to the market.  They are raising the game, aren't they?  And forcing the competition to increase value or get pushed aside.  I really like my DP832.  I think it's funny that people complain about the rotary knob and circular arrangement of numbers without having ever having used one (I got used to it quickly and now I like it maybe more than a traditional keypad - it's easier to hover my hand over the knob and make any adjustments I need).  But the same folks who complain that the knob isn't as good as it could be justify other PSU's not even having knobs at all because they aren't gimmicky?

It's a giant pain in the ass to set OCP/OVP or even to set the voltage and current levels on my Agilent or Fluke supplies compared to the Rigol.  I understand that engineers are infinitely picky, but some of the complaints aired seem to me to be akin to bitching about how the traction control in race mode in the new Ferrari 458 doesn't let you slide the ass end of the car enough before it kicks in, as you drive your 1994 Corvette  :-DD

The power spike at turn on *is* a genuine concern and while it won't have any effect on the stuff I do, it shouldn't happen... on the other hand, has anyone checked their 832 to see if it does the same thing?  Do we know something isn't wonky with Dave's unit?  Or maybe his is better than most and others spike to 20V?  Maybe it's not a design fault but something else?

Hey Corp,

Agree with your observations and comments on the 832 user interface; I'm betting people who move from the "traditional" layout and features will come to see that not only is the 832 "ok" but that it offers a lot capabilities they wouldn't want to give up.   

Hopefully someone can run some further tests on the spike thing; as you say, until we get some more info it could be a variety of things.  Whatever it is, it would be great to isolate it/understand it and maybe also nice to hear something from Rigol about it.
 

Offline rf-loop

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #193 on: August 22, 2013, 05:03:41 am »
After all, what good is that voltage sense input if your spec is 0.6% on a typical 3.3V output.


Load Regulation Rate ±(Output Percentage + Offset)
Voltage <0.01%+2mV



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Offline ElectroIrradiator

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #194 on: August 22, 2013, 05:09:47 am »
Displaying the values for all channels at the same time.

Would tend to agree with that. Anything else?
 

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #195 on: August 22, 2013, 05:11:26 am »
After all, what good is that voltage sense input if your spec is 0.6% on a typical 3.3V output.
Load Regulation Rate ±(Output Percentage + Offset)
Voltage <0.01%+2mV

Here is the banner spec:
Quote
Programming Accuracy at 25°C ±5°C
Voltage: 0.05% + 20 mV, 0.05% + 20 mV, 0.1% + 5 mV
+ Current: 0.15% + 4 mA, 0.15% + 4 mA, 0.2% + 10 mA

Quote
Readback Accuracy at 25°C ±5°C
Voltage: 0.05% + 10 mV, 0.05% + 10 mV, 0.1% + 5 mV
Current: 0.15% + 4 mA, 0.15% + 4 mA, 0.2% + 10 mA
 

Offline FrankBuss

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #196 on: August 22, 2013, 05:43:06 am »
The power spike at turn on *is* a genuine concern and while it won't have any effect on the stuff I do, it shouldn't happen... on the other hand, has anyone checked their 832 to see if it does the same thing?  Do we know something isn't wonky with Dave's unit?  Or maybe his is better than most and others spike to 20V?  Maybe it's not a design fault but something else?
Looks like it is a fault by design, see https://www.eevblog.com/forum/blog/eevblog-509-rigol-832-lab-power-supply/msg278118/#msg278118 Has anyone asked Rigol about it, if they don't watch Dave's channel, and if they know a quick fix for it?
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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #197 on: August 22, 2013, 06:31:18 am »
Looks like it is a fault by design, see https://www.eevblog.com/forum/blog/eevblog-509-rigol-832-lab-power-supply/msg278118/#msg278118 Has anyone asked Rigol about it, if they don't watch Dave's channel, and if they know a quick fix for it?

The local rep has said he'll get Rigol to take a look at it. These Chinese companies cannot access youtube etc.
 

Offline rf-loop

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #198 on: August 22, 2013, 06:47:37 am »
After all, what good is that voltage sense input if your spec is 0.6% on a typical 3.3V output.
Load Regulation Rate ±(Output Percentage + Offset)
Voltage <0.01%+2mV

Here is the banner spec:
Quote
Programming Accuracy at 25°C ±5°C
Voltage: 0.05% + 20 mV, 0.05% + 20 mV, 0.1% + 5 mV
+ Current: 0.15% + 4 mA, 0.15% + 4 mA, 0.2% + 10 mA

Quote
Readback Accuracy at 25°C ±5°C
Voltage: 0.05% + 10 mV, 0.05% + 10 mV, 0.1% + 5 mV
Current: 0.15% + 4 mA, 0.15% + 4 mA, 0.2% + 10 mA

Sense is not for Readback accuracy nor Programming accuracy.
Why you answer with these? When there is load regulation, one  important parameter of regulated precision power supply.

Sense is part of regulation loop. 
It is for feedbac real voltage in  point what is important to regulate. Now this PSU regulate only its output terminals (if internal senses are connected directly to terminals in front panel).

Do we really need talk what is external "sense" function.

Of course it is not  important if we only look PSU output terminals.  In normal practical use after terminals are leads to load. Im not interested PSU terminals. I'm interest what my Load "see". (if do something what need care this)

Of course if load is constant there is not so much need for sense. Voltage drop in leads is meaningless becouse IF need accurate voltage it can measure from load terminals with external meter when there is this load current.

Situation is very different if there is variable load and need keep voltage constant independent of load variations. And PSU what do not have feedback from this point is blind.

Example: If there is 1A variation in load and we have 1m cable (total 2m wire) 1.0 mm2  copper wire there is around 0.033V drop.  If our Vout in PSU output terminal is 3.3V without load change, after our cable variation is around 0.033V. 
1% is now quite far away from 0.01% load regulation.

And 1mm2 copper is not very common. Many times test leads are less. How about if wire lenght from supply to load is more, and current variations is more.

Of course if 1m distance need 100mm2 copper rods for keep 0.01% load regualtion for 1A changes, then no need external senses if this load regualtion is important keep this very low level. Totally other question is who need this.

Of course this kind of things are not relevant if load is bulb or some battery operated equipment or something other simplest things for PSU. 

If practice and theory is not equal it tells that used application of theory is wrong or the theory itself is wrong.
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Harmony OS
 

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Re: EEVblog #509 - Rigol 832 Lab Power Supply
« Reply #199 on: August 22, 2013, 07:17:06 am »
Sense is not for Readback accuracy nor Programming accuracy.
Why you answer with these?

Because it determines the basic accuracy of the power supply!
Forget about sense or no sense, I'm talking about the basic DC accuracy display of the power supply, which someone complained was not very good on the Rigol. I was just showing that it's no better on the Agilent.
 


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