Rigol DP832 - Firmware list and bugs

[LaurentR]

My DP832, firmware 01.14 is still recognized trough USB and LAN under Keysight Connection Expert.

Thanks, OldNeurons!.  Following your positive feedback I re-flashed the 01.14 firmware, and this time no problems for Keysight Connection Expert to detect the DP832 via USB!  A mystery whatever happened the first time...  I have updated my post above.

I tried LAN connection but Connection Expert still does not see it.  Rigol UltraSigma does find it, though, and DP832 responds to SCPI commands that way.

Does anyone control DP832 via LAN connection and have any news about doing so?

Sparky

I have also lost the auto-find on the LAN with I/O Libraries, but adding the IP address manually works fine. Go figure.

[LaurentR]

My DP832, firmware 01.14 is still recognized trough USB and LAN under Keysight Connection Expert.

Thanks, OldNeurons!.  Following your positive feedback I re-flashed the 01.14 firmware, and this time no problems for Keysight Connection Expert to detect the DP832 via USB!  A mystery whatever happened the first time...  I have updated my post above.

I tried LAN connection but Connection Expert still does not see it.  Rigol UltraSigma does find it, though, and DP832 responds to SCPI commands that way.

Does anyone control DP832 via LAN connection and have any news about doing so?

Sparky

I have also lost the auto-find on the LAN with I/O Libraries, but adding the IP address manually works fine. Go figure.

Just to ruin my day, I also updated my DS1074Z and lost the SCPI connection through USB... Works fine with just NI-Visa, but doesn't work anymore with I/O Libraries installed. LXI works, but doesn't auto-scan either. I wonder if they just rewrote part of their SCPI stack and dinged several of the firmware.

[eelliott]

My DP832, firmware 01.14 is still recognized trough USB and LAN under Keysight Connection Expert.

Thanks, OldNeurons!.  Following your positive feedback I re-flashed the 01.14 firmware, and this time no problems for Keysight Connection Expert to detect the DP832 via USB!  A mystery whatever happened the first time...  I have updated my post above.

I tried LAN connection but Connection Expert still does not see it.  Rigol UltraSigma does find it, though, and DP832 responds to SCPI commands that way.

Does anyone control DP832 via LAN connection and have any news about doing so?

Sparky

I have also lost the auto-find on the LAN with I/O Libraries, but adding the IP address manually works fine. Go figure.

After updating my DP832 from 01.09 to 01.14, Connection Expert found my LAN-connected DP832 with no problem.  (I/O Libraries 17.1.19313.5)  I can't recall if I manually defined the DP832's IP address to Connection Expert a long time ago (I recall doing this for at least one instrument but don't remember if it was the DP832.)  One thing I did notice was that Connection Expert initially displayed a red X next to the DP832's Visa Address (but both Start Instrument Web Interface and a Start Command Expert IDN? command worked).  After rebooting the PC the red X changed to a green check mark.

So Connection Expert seems to be working fine for me over the LAN with 01.14.  However, my custom NI-VISA C# program failed to connect whereas it had worked fine yesterday with firmware 01.09.  NI IO Trace revealed an error which said that the resource was not found.  The search initiated by clicking on "Network Devices" in NI-MAX did not find the DP832.  But right-clicking on "Network Devices" in NI-MAX and clicking "Create New Visa TCP/IP Resource..." initiated a search which found the DP832. I completed the creation process to add the DP832 to NI-MAX's list.  Then my custom program worked fine.  It is a mystery to me as to what has changed and why one of NI-MAX's searches found the DP832 but the other NI-MAX search did not.  Another mystery is why it is now necessary to define the DP832 to NI-MAX; the C# NI-VISA resourceSearch string is very specific: "TCPIP0::192.168.10.43::inst0::INSTR".

[Howardlong]

Would someone kindly point me to where I can download 1.14 firmware from please? I have an OCP problem on my unit I'd like to remedy.

Many thanks!

[OldNeurons]

Would someone kindly point me to where I can download 1.14 firmware from please? I have an OCP problem on my unit I'd like to remedy.

Many thanks!

PM sent with link to firmware 1.14.

[Howardlong]

Would someone kindly point me to where I can download 1.14 firmware from please? I have an OCP problem on my unit I'd like to remedy.

Many thanks!

PM sent with link to firmware 1.14.

Thank you!

I am delighted to report that the OCP problems I encountered (documented here https://www.eevblog.com/forum/testgear/rigol-dp832-firmware-updates-and-bug-list/msg628640/#msg628640) are now a thing of the past! I was concerned that when I replaced a MOSFET in the unit a few weeks ago I'd broken something, but thankfully it appears not.

One thing to note was that the bootloader part of the firmware update seemed to just hang, so I went straight to the main update and analog board updates, it appears to have worked.

Thanks again.

[cidak]

To all owners of DP8xxx. 

I would like to ask those who have a DPxxx Rigol it may do a test to compare if it's a problem of my power unit, or if there is a firmware bug general.

The test is the following: 
by any value set at the output (for example 1 Volt) increase the voltage of 1 mV at a time, measure the output with a DMM  external if indeed the intention output rises to 1 mV at each step, or as in my case increases 0.6 mV and the next step in a 1.4 mV (total actual doing of the two steps 2 mV). 

So every 2 steps it the 2mV correct but to every single-step one is from 0.6 mV and the other from 1.4 mV. This is repeated alternately 0.6 /1.4 ~ 0.6 /1.4 etc.

Thanks

[bson]

Cidak, if you want 1V and want to adjust it in 1mV steps, then I'd use CH3.  CH1&2 may not have sufficient DAC resolution to make 1mV adjustments and what you see is consistent with rounding error.  I always use CH3 for these sort of low-voltage experiments.

[Belgarion]

To all owners of DP8xxx. 

I would like to ask those who have a DPxxx Rigol it may do a test to compare if it's a problem of my power unit, or if there is a firmware bug general.

The test is the following: 
by any value set at the output (for example 1 Volt) increase the voltage of 1 mV at a time, measure the output with a DMM  external if indeed the intention output rises to 1 mV at each step, or as in my case increases 0.6 mV and the next step in a 1.4 mV (total actual doing of the two steps 2 mV). 

So every 2 steps it the 2mV correct but to every single-step one is from 0.6 mV and the other from 1.4 mV. This is repeated alternately 0.6 /1.4 ~ 0.6 /1.4 etc.

Thanks

These are my results:

DP832 set value (channel 1)	Measured on DMM
1.000V	1.001295V
1.001V	1.002326V
1.002V	1.003329V
1.003V	1.004366V
1.004V	1.005366V
1.005V	1.006410V

DP832 set value (channel 3)	Measured on DMM
1.000V	1.000869V
1.001V	1.001894V
1.002V	1.002943V
1.003V	1.003981V
1.004V	1.005005V
1.005V	1.006063V

[LaurentR]

To all owners of DP8xxx. 

I would like to ask those who have a DPxxx Rigol it may do a test to compare if it's a problem of my power unit, or if there is a firmware bug general.

The test is the following: 
by any value set at the output (for example 1 Volt) increase the voltage of 1 mV at a time, measure the output with a DMM  external if indeed the intention output rises to 1 mV at each step, or as in my case increases 0.6 mV and the next step in a 1.4 mV (total actual doing of the two steps 2 mV). 

So every 2 steps it the 2mV correct but to every single-step one is from 0.6 mV and the other from 1.4 mV. This is repeated alternately 0.6 /1.4 ~ 0.6 /1.4 etc.

Thanks

Look at this post (and the attached histogram) for the statistical result of a full sweep showing in no uncertain term the DAC step size. Also see the rest of the thread for linearity data:
https://www.eevblog.com/forum/testgear/noob-dac-linearity-in-the-dp832/msg584141/#msg584141

I haven't run the same analysis on Ch3, so I can't confirm if Ch3 has indeed better granularity.
Of course, note that this is all way within specs of the DP832.

[LaurentR]

Just found time to run a full 1mV sweep of Ch3.

And the answer is... yes, Ch3 has better granularity. Eyeballing the data, it seems to have about 0.22mV granularity, which is a bit more than twice as small as Ch1. See histogram attached. I should have added axis titles, but the histogram is of the measured voltage difference between two consecutive steps (separated by 1mV, the programming granularity). The peaks show that the distance is usually around 1.045mV, and if not, most likely around 0.83mV (and extremely infrequently around 1.25mV), thus the derivation of the DAC granularity.

Note that actual absolute accuracy and linearity are much worse than this, so I don't think that this has practical applications. On my home-calibrated DP832, Ch3 stays within about +/- 1.5mV of programmed value throughout the whole sweep, which is quite good.

[bson]

Nice to see some actual data!

I agree on absolute accuracy - it's good but not down to 1mV.  It probably varies from unit to unit; on mine (also DIY calibrated) CH3 is ridiculously precise and always accurate to 1mV.  Today though I needed 14.5V and dialed in CH1, and ended up reading 14.498. (Which is pretty damn good in itself.)  Put a DMM (34465A) on it, which also read 14.498.  So ticked it up 2mV to 14.502V and got 14.500V out.  Nice! 

I was using one of these below to compare an Agilent 34401A (scored for $350!) to the 34465A.  According to the seller, my 10V reference is 0.37ppm low.  The 34465A reads it 6.7ppm high; the 34401A 24ppm high.  All good enough for government work!  Didn't try null measuring -- really should get myself a cheap microammeter, and maybe better leads than my $6 Pomonas, so it's not as super accurate as it could be, but I just wanted a quick ballpark check of the 34401A, relative to the 34465A...  Here's the reference - highly recommend it.  http://www.ebay.com/itm/10-VDC-2ppm-Precision-Voltage-Reference-Standard-Nulled-to-Fluke-732A-or-732B-/251756273626?pt=LH_DefaultDomain_0&hash=item3a9dd7dfda

[LaurentR]

Nice to see some actual data!

I agree on absolute accuracy - it's good but not down to 1mV.  It probably varies from unit to unit; on mine (also DIY calibrated) CH3 is ridiculously precise and always accurate to 1mV.  Today though I needed 14.5V and dialed in CH1, and ended up reading 14.498. (Which is pretty damn good in itself.)  Put a DMM (34465A) on it, which also read 14.498.  So ticked it up 2mV to 14.502V and got 14.500V out.  Nice! 

I was using one of these below to compare an Agilent 34401A (scored for $350!) to the 34465A.  According to the seller, my 10V reference is 0.37ppm low.  The 34465A reads it 6.7ppm high; the 34401A 24ppm high.  All good enough for government work!  Didn't try null measuring -- really should get myself a cheap microammeter, and maybe better leads than my $6 Pomonas, so it's not as super accurate as it could be, but I just wanted a quick ballpark check of the 34401A, relative to the 34465A...  Here's the reference - highly recommend it.  http://www.ebay.com/itm/10-VDC-2ppm-Precision-Voltage-Reference-Standard-Nulled-to-Fluke-732A-or-732B-/251756273626?pt=LH_DefaultDomain_0&hash=item3a9dd7dfda

Ch3 is substantially better than Ch1. Just like Ch1, it's mostly very good (and within 1mV), but has some interesting peaks and valleys that extend to 1.5-2mV. See plot below.
That's a full 1mV sweep measured by a 34465A.

[cidak]

To all owners of DP8xxx. 

I would like to ask those who have a DPxxx Rigol it may do a test to compare if it's a problem of my power unit, or if there is a firmware bug general.

The test is the following: 
by any value set at the output (for example 1 Volt) increase the voltage of 1 mV at a time, measure the output with a DMM  external if indeed the intention output rises to 1 mV at each step, or as in my case increases 0.6 mV and the next step in a 1.4 mV (total actual doing of the two steps 2 mV). 

So every 2 steps it the 2mV correct but to every single-step one is from 0.6 mV and the other from 1.4 mV. This is repeated alternately 0.6 /1.4 ~ 0.6 /1.4 etc.

Thanks

These are my results:

DP832 set value (channel 1)	Measured on DMM
1.000V	1.001295V
1.001V	1.002326V
1.002V	1.003329V
1.003V	1.004366V
1.004V	1.005366V
1.005V	1.006410V

DP832 set value (channel 3)	Measured on DMM
1.000V	1.000869V
1.001V	1.001894V
1.002V	1.002943V
1.003V	1.003981V
1.004V	1.005005V
1.005V	1.006063V

Thank you for your quick and accurate response.
Ok, your Log on measured voltages in steps of 1 mV, seems to be perfect.
So I hom a problem it seems, because as explained initially each time increment of 1 mV ago the first increase 1.3mV and 0.7mV per second increase.
I calibrated DAC and ADC repeatedly my DP but the error is always the same.
I noticed, however, that when the output is turned off (or if you set the output voltage to 0V.) Offset output terminals is 0.550mV ~. Someone can do this check, please?
Thanks.

[cidak]

Thanks to the attached chart.

This measure seems to bring error very rarely.
In my case, the error is fixed over the entire range in output from 0 to 42 volts (my model is a DP811A).
Via software or hardware, How can you adjust this? You think?

[LaurentR]

Thank you for your quick and accurate response.
Ok, your Log on measured voltages in steps of 1 mV, seems to be perfect.
So I hom a problem it seems, because as explained initially each time increment of 1 mV ago the first increase 1.3mV and 0.7mV per second increase.
I calibrated DAC and ADC repeatedly my DP but the error is always the same.
I noticed, however, that when the output is turned off (or if you set the output voltage to 0V.) Offset output terminals is 0.550mV ~. Someone can do this check, please?
Thanks.

I don't see a problem with any of what you mention. Keep in mind that the accuracy specs for the DP811A are: 0.05% + 10mV. I don't see anything you've explained violating this spec. It's all way within spec, unless I missed something.

First, you have a DP811A. Over the 40V range with the 16b DAC, you can expect ~45V/64k = 0.69 mV resolution, which is what you see, so, as you program your 1 mV steps, it will be totally normal for the supply to jump by 0.69 mV or 2x0.69 mV as needed to get as close to the programmed value as possible. This closely matches the behavior you are describing.

The DP832 may offer slightly better resolution from its smaller range (~0.55mV on 30V and ~0.22 on 5V), but it's the same principle.

As far as the offset at 0, a quick look at my data shows that the very accurate Ch3 has a -0.29mV offset at 0. It's pretty common for the supplies to be slightly off at 0V (more so than later), but it's still completely within specs. I don't see a problem either.

[Macbeth]

Here's the reference - highly recommend it.  http://www.ebay.com/itm/10-VDC-2ppm-Precision-Voltage-Reference-Standard-Nulled-to-Fluke-732A-or-732B-/251756273626?pt=LH_DefaultDomain_0&hash=item3a9dd7dfda

Oh wow,  the Calibratory D-105 is back! It looks like our Awesome friend has upped his prices too.

Have you opened it to check if the build quality has improved at all?


That flakey piece of foil is all part of the magic apparently. Oh, don't open it as apparently that ruins the calibration. I think it's something to do with Schrodinger's cat and quantum entanglement. Don't worry, apparently GOD gave the inventor the inspiration to develop this standard, so you can be guaranteed that 2ppm accuracy. No need to open it or question how it works. Faith is all you need.

Was it the wall of text in the ebay advert or the presentation of testimonials that impressed you so much?

[bson]

Was it the wall of text in the ebay advert or the presentation of testimonials that impressed you so much?

I'm not really interested in a bunch of children's pissing matches.  There's no need to be rude.  It's a rinky-dink $100 toy device (I think that's what I paid for it) and it has drifted absolutely none at all the last four months relative to my instruments.  Of course, it may all have drifted together, and no matter how unlikely or implausible, the only way to achieve mathematical certainty is by testing against an proper standard.  However, under the assumption that all my instruments of a variety of ages aren't all drifting in unison, it's perfectly fine what it does and I wouldn't hesitate to recommend it.  If this affronts you hoity-toity ivory-tower sense of superiority, so be it.  I couldn't give a damn.

[cidak]

Here's the reference - highly recommend it.  http://www.ebay.com/itm/10-VDC-2ppm-Precision-Voltage-Reference-Standard-Nulled-to-Fluke-732A-or-732B-/251756273626?pt=LH_DefaultDomain_0&hash=item3a9dd7dfda

Oh wow,  the Calibratory D-105 is back! It looks like our Awesome friend has upped his prices too.

Have you opened it to check if the build quality has improved at all?


That flakey piece of foil is all part of the magic apparently. Oh, don't open it as apparently that ruins the calibration. I think it's something to do with Schrodinger's cat and quantum entanglement. Don't worry, apparently GOD gave the inventor the inspiration to develop this standard, so you can be guaranteed that 2ppm accuracy. No need to open it or question how it works. Faith is all you need.

Was it the wall of text in the ebay advert or the presentation of testimonials that impressed you so much?

The is OT discussion in area "DP832 Firmware list and bugs"

[pascal_sweden]

For your list of bugs and design flaws in the DP832: Youtuber Jason Li investigated that Rigol's DP832 seems not to be isolated to earth. There's an AC coupling between earth and ground (exceed 32 Vac). Here's the video:

Is this problem fixed in the mean time?

[mcinque]

@pascal_sweden:

As Dave said:

...
I don't see the issue, you'll get this with almost any supply, capacitive coupling between output and mains earth is quite normal.
...
If for some reason this is an issue with your system, mains output reference your supply, that is what the earth terminal is on the front panel for.

[pascal_sweden]

The guy on the video did mains output reference his supply, as you can see with the yellow cabling in the video.

[mcinque]

When he's doing all his tests and reads high voltages, isn't the yellow cable disconnected from the earth terminal?

[pascal_sweden]

Yes, you are right! I can also see a "crack" in the chassis of the power supply on the left down side.
Looks like he had some issue with the chassis.

[Andy Watson]

For your list of bugs and design flaws in the DP832: Youtuber Jason Li investigated that Rigol's DP832 seems not to be isolated to earth. There's an AC coupling between earth and ground (exceed 32 Vac). Here's the video:

Is this problem fixed in the mean time?

Is it a problem? Unless there is a significant current flowing I would say that it is not a problem, it is typical "pick up" that you will find in any environment where mains AC fields are present. Quality power supplies employ a transformer with an electrostatic screen to reduce mains coupling, but it is still possible for capacitive coupling to occur on the internal wiring.