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Products => Test Equipment => Topic started by: Wolfgang on August 25, 2018, 03:16:23 pm

Title: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 25, 2018, 03:16:23 pm
Hi,

I use RIGOL equipment a lot, and in the beginning I liked it because it just worked and did what I wanted. If there was an issue,
they were fast and helpful. See here

https://electronicprojectsforfun.wordpress.com/test-equipment/

to check what I use.

In the recent past, however, there were some findinds where I found RIGOL equipment not to all that great, on several occasions:

- the DSG815 and DSG830 RF generators have a rather unclean modulation quality
https://electronicprojectsforfun.wordpress.com/test-equipment/test-equipment-measurements/rf-signal-generator-am-modulation-quality/

- the non-IQ pro model RF generator DSG3060 is fine but the IQ modulation in the DSG3060IQ model was strongly out of balance, with no
way to manually even this out like on the Keysights. Moreover, the minimum carrier frequency for the DSG3060IQ is 50MHz.
https://electronicprojectsforfun.wordpress.com/test-equipment/test-equipment-measurements/rf-signal-generator-iq-modulation-quality/

- the last issue I had (and still have) is the M300 data logger MC3324 combined voltage / current measurement card. It *disrupts* the current of a DUT with every measurement cycle. I reported this as a severe bug.

Well, any manufacturer has issues, and normally they correct that. In my case, *nothing* has been done. I asked, and they said that the DSGs will  not be changed, and for the M300 problem I got the answer that had no resources to work on this problem.

I remember some old times when Dave Jones found some design flaws in a DP832, and RIGOL replaced the mainboards for all users and redesigned it. This - at least for me - was a good argument to buy from this company.

Whats your impression today with RIGOL products and support today ?




-
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: chickenHeadKnob on August 25, 2018, 07:04:57 pm
I have no insight as to what is happening inside Rigol, however it is routine that products nearing the end of their market life cycle are essentially orphaned. At the time of Dave's review the 832 was newly introduced, and Dave is very high profile. They couldn't ignore him. So using Dave's video as an indicator of future support is a hazardous extrapolation. Around the same time the 832 came out there were youtube reviews of the DS40xx (Conner Wolf I think) complaining about unfixed bugs and callous support. Life is unfair.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 25, 2018, 07:18:53 pm
Maybe you're right, but then my recommendation to buy RIGOL products when:

- they have a high volume only
- they are more than 1 year on the market
- critiques and reviews are very positive

is essentially correct. On the other hand, RIGOL wants to play with the big boys. With a quality and support standard like
this it will not happen so easily.

So, RIGOL mass products OK, more expensive, pro or exotic stuff - beware.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Mr. Scram on August 25, 2018, 07:39:06 pm
Maybe you're right, but then my recommendation to buy RIGOL products when:

- they have a high volume only
- they are more than 1 year on the market
- critiques and reviews are very positive

is essentially correct. On the other hand, RIGOL wants to play with the big boys. With a quality and support standard like
this it will not happen so easily.

So, RIGOL mass products OK, more expensive, pro or exotic stuff - beware.
Both Rigol and Siglent have trouble understanding that being a serious contender means building long term relationships, or providing consistent support. I've been told by people with more experience in dealing with Chinese manufacturers that they're not used to investing in long term relationships and that this is a still developing mentality.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 25, 2018, 07:41:14 pm
... probably a good explanation of their current mindset. Support only when you must or the public disgrace is too painful.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Mr. Scram on August 25, 2018, 07:45:07 pm
... probably a good explanation of their current mindset. Support only when you must or the public disgrace is too painful.
It should be noted that western mentality seems to be declining when it comes to warranty and long term customer relationships. Very few companies are going out of their way to be properly helpful and a lot of once decent brands are bought and forced to reduce product quality.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 25, 2018, 07:51:16 pm
... thats why I like my old-style boatanchored Keysight stuff (E5071C, N9000A, DSOS0604A, N5171/72B, 34465A...) so much. They are *not* modern. But they stood the test of time, and their bugs are mostly gone. I can do without Windows10, fingerprints on my screens, animated gimmicks and software catastrophies like BenchVue (looks like a hopelessly misdesign space invaders GUI). 3 years warranty are a must.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: bitseeker on August 25, 2018, 07:54:41 pm
... mass products OK, more expensive, pro or exotic stuff - beware.

Yeah, that's a good generalization. More eyeballs = more problems detected and higher pressure to fix them.

Even the DS1054Z took a few years to get the kinks worked out. The "bleeding edge" is aptly named and a pain to ride on.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: imo on August 25, 2018, 08:31:18 pm
All those Chinese companies you write about were founded ~20-30y ago by HP, IBM, Tek, .. as their cheapest production sites. Since then the guys gathered good manufacturing skills, learned a bit of R&D, and they started to produce their own products.

They still are lacking what their "big founders" possessed at the time the production in China started, however,  - a large world-wide customer's support organizations (quite expensive, btw.).

And while the original "big founders" see these smaller far-east manufacturers are pretty successful with their today's business model (a cheap mass production with "as-is" level of quality), they slowly start to accommodate their model too..  :)
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Bud on August 25, 2018, 08:37:11 pm
... probably a good explanation of their current mindset. Support only when you must or the public disgrace is too painful.

I am sure the Chinese do not give crap about any of these two.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 25, 2018, 08:40:12 pm
... at the low end the Chinese are tough competitors, because

- their *mass* products usually work
- they are "good enough" for most applications, say 95%
- a premium brand instrument costs a lot more for the same performance. What it can do extra is rarely needed.

At the high end - different story. Users are much more intolerant for bugs and silly errors. And they want a clean record
with long-term support.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 25, 2018, 08:43:36 pm
I would not be so sure that they can completely ignore reviews and user response.
At the long run, its your good reputation that makes people buy your stuff.

If you once bought some junk from a manufacturer or had lousy support, your learning curve will prevent another buy.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: nctnico on August 26, 2018, 11:31:19 am
... at the low end the Chinese are tough competitors, because

- their *mass* products usually work
- they are "good enough" for most applications, say 95%
- a premium brand instrument costs a lot more for the same performance. What it can do extra is rarely needed.
That is true. Unfortunately for me it meant buying the premium brand equipment in the end a couple of times already. It is frustrating because time & money are wasted and projects get delayed.

If you once bought some junk from a manufacturer or had lousy support, your learning curve will prevent another buy.
I'm done buying the 'cheaper' pieces of test equipment when it comes to more complex types of equipment because in the end they don't deliver.

The Chinese will continue to sell low quality equipment because there is a sucker born every minute. Most people just can't ignore a lower price for something which seems to deliver the same at first glance.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: rstofer on August 26, 2018, 06:09:09 pm
The Chinese will continue to sell low quality equipment because there is a sucker born every minute. Most people just can't ignore a lower price for something which seems to deliver the same at first glance.

Or the buyers are hobbyists with low requirements and lacking in the sophistication to miss the more advanced features.

One needs to separate production from hobby.  For the hobbyist, Rigol is probably good enough (at least I like my 1054Z and 832).  But my needs are modest!  It's just a hobby!  And it's not my most expensive hobby.

In a commercial setting, I wouldn't have Rigol or Siglent or any of the other off-brands in the building - at any level.  It would be Tektronix, Keysight and Fluke - nothing but the best when the investment is tax deductible,  even if it is only the appearance of 'best'.  I'm not sure of this but I'll bet the military contractors in the US are not using Rigol.  But it's just a guess...  Not a bad guess considering the contractually required calibration cycles.  I like my Aneng 8008 but I doubt if it could be used on an F35.

Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: bugi on August 26, 2018, 08:59:14 pm
I like my Aneng 8008 but I doubt if it could be used on an F35.
Couldn't resist... considering the reputation of the F35 development and results, they probably did use at least some Anengs during the project  ::)

Also, there are things even in high quality production that could be completed just as well (and without breaking standards or whatnot) with any crap device(s), given just minor precautions. However, getting off topic so I'll leave the rest of that to each others imagination.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: lordvader88 on August 27, 2018, 01:52:46 pm
LOL bugi, yup, windows8 and DSO 138 scopes

I'm hoping the engines and airframes are built better
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: dr.diesel on August 27, 2018, 02:35:05 pm
I contacted support many times during the 4000 series fiasco, it was a horrible experience.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Bud on August 27, 2018, 04:11:49 pm
You cant change the Culture overnight. It will take another generation or two, providing it is paid attention to. Which i do not think it is.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: GregDunn on August 27, 2018, 04:51:56 pm
I think it's been pointed out on these forums several times that the Chinese manufacturers will sell you what you want to buy.  If you want cut-rate cheap hardware, they'll sell it to you.  If you want well-built, quality gear, they'll sell that too.  Don't expect quality at the very lowest prices though.  The hobbyists are buying the low priced equipment in droves, and it's good enough for 90% of hobby use.  Lots of people expect that a full-featured piece of test gear has to be top notch quality, but that's not how it works when you're designing to a specific price.

Heck, the low end Tektronix scopes are made in China too - does that mean Tek scopes are considered crap now? (that's not a troll; the answer may well be 'yes' around here)
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 27, 2018, 05:04:07 pm
... the really cheap, mass produced stuff seems to be of a lesser problem nowadays because the seem to have got the bugs out by now (DP832,DSA815,DG1000Z,MSO1000Z).

The problems start with stuff that is not all that cheap anymore (DSG815/830,DSG3060IQ,M300, ...) and where they claim that they can play with the big boys.
They cant, and pro users will not tolerate silly bugs or bad service. The price difference from them to a (rebated) Keysight is simply to small, IMHO.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: rsjsouza on August 27, 2018, 07:01:38 pm
Wolfgang, I have a DS4014 purchased from their US clearance store (early 2015) and I had great support from them in the purchase process and information about new firmware (I have never had to use their service). I intercepted the end of their development and support cycle for this family of oscilloscopes, therefore I saw only two firmware updates but the product was overall very stable - many other users of the same family had worse experiences as their purchases were made at much earlier stages of the product lifecycle and the firmware updates were very scarce. Users of their former flagship model DS6000 seem to have suffered a lot more, as this product seems to be in a much less finished state.

Therefore this is a datapoint that shows their service has been spotty for quite a while, but they seem to have released firmware updates for their entry families DS2000 and DS1000Z at a much faster rate. I can't comment as I don't have them, but I suggest you to follow how they manage their new flagship model DS7000 family.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 27, 2018, 07:24:13 pm
... Nice that you did not got into heavy rain with the DS4014 you bought. As you write, others have suffered a lot more.

I got really sceptical about their "pro" stuff. Up from, say 2000€ people (including myself) think one more time before they buy.
The DS7000 scope series is even more than that, and users in this price range expect a better quality and also timely fixes if something is wrong.

Lets see what Dave will find out, and I will wait one year minimum to see what the "early adopters" have to say about it.

Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: thm_w on August 27, 2018, 08:00:51 pm
- the last issue I had (and still have) is the M300 data logger MC3324 combined voltage / current measurement card. It *disrupts* the current of a DUT with every measurement cycle. I reported this as a severe bug.

Weird if you look at how they've drawn the block diagram, it seems like that should not be possible. I also don't see the current shunts on the board itself. Are they using the relays to interrupt the shunt somehow?

Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 27, 2018, 08:07:15 pm
... exactly. The schematics looks nice, but what they do is rip open the bridging relay before the connection to the multimeter current input (including the shunt) is established.
To me it looks like a beginners fault when programming the relay timing. Unfortunately, they refuse to work on this bug.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: nctnico on August 27, 2018, 08:11:27 pm
... exactly. The schematics looks nice, but what they do is rip open the bridging relay before the connection to the multimeter current input (including the shunt) is established.
To me it looks like a beginners fault when programming the relay timing. Unfortunately, they refuse to work on this bug.
And how about returning it?
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: rsjsouza on August 27, 2018, 08:22:38 pm
... exactly. The schematics looks nice, but what they do is rip open the bridging relay before the connection to the multimeter current input (including the shunt) is established.
To me it looks like a beginners fault when programming the relay timing. Unfortunately, they refuse to work on this bug.
Wow, that is a pretty fundamental error which prevents usability.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 27, 2018, 08:24:28 pm
I did. They gave me a M302 model to continue my tests. This is a voltage/resistance only card with 20 channels. I made a shunt resistor to measure the current via the burden voltage. We still have to negotiate how to proceed, I still have the right to return it.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 27, 2018, 08:27:45 pm
... correct. I simply did not believe that they could be so silly. The M300 is on the market for a few years now ..  :--
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: 2N3055 on August 27, 2018, 09:24:31 pm
Regarding M300, if you want switching between different inputs, connected to different circuits, you HAVE TO break before make.. Or you will shortcut different circuits...
Only way to do it without breaking is to have several shunts, one for every input. On schematic, there is something that looks like a short link. Maybe place for shunt?
Or you could have duplicate relay, that will make a short IN1, than brake IN1, make IN2, unshort IN2....

But you have to break one input before make other, otherwise BOOM...

What scanner card from other manufacturer can do switching of current measurements, using meter internal current shunts and that doesn't break before make?
That would be interesting info..
Regards,

Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 27, 2018, 09:31:46 pm
... break before make for voltage inputs is fine and logical. The M300 always measures one channel fter the other, one by one.

For current channels it *should* work like this:
- leave input relay in bridge mode (see schematics)
- disconnect relay between input and meter for all current channels
- close connection from current channel to shunt inside meter
- open input relay and measure
- close input relay
- open connection from current channel to shunt inside meter

... next measurement.

If you are in autoscale mode, it would be OK if the lowest value shunt is tried first, but always with input shorted between shunt resistor changes, of course.

Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: 2N3055 on August 27, 2018, 09:40:38 pm
... break before make for voltage inputs is fine and logical. The M300 always measures one channel fter the other, one by one.

For current channels it *should* work like this:
- leave input relay in bridge mode (see schematics)
- disconnect relay between input and meter for all current channels
- close connection from current channel to shunt inside meter
- open input relay and measure
- close input relay
- open connection from current channel to shunt inside meter

... next measurement.

If you are in autoscale mode, it would be OK if the lowest value shunt is tried first, but always with input shorted between shunt resistor changes, of course.

So shorting link in schematic is a separate relay? In that case it is second case I mentioned and it should be possible i that relay can be controlled separately.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on August 27, 2018, 10:09:40 pm
... I think the hardware is fine, only the programmers have no idea about electronic measurement practices  :-DD

Update 30.8.2018: RIGOL Germany agreed to pay me a decent measurement shunt because they could not fix the M300 problem. Although this is not optimal, I agreed to that. At least thats some support to get the customer out of a problem.

Lesson: Stay away from the MC3324 card, and ask RIGOL for a free shunt in case you need to measure currents with the normal MC3120 voltage card. This one seems to work nicely.
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: TurboTom on September 27, 2018, 09:34:00 am
... exactly. The schematics looks nice, but what they do is rip open the bridging relay before the connection to the multimeter current input (including the shunt) is established.
To me it looks like a beginners fault when programming the relay timing. Unfortunately, they refuse to work on this bug.

I've got the same combination running here and since I'm rewiring a setup currently, I used the opportunity to do some testing to try to replicate your findings. My firmware versions of the relevant components are:

M300 (Mainframe) - 00.02.00.08.00
MC3065 (DMM) - 06.01.01.25
MC3324 (MPX) - 00.01.01.03

Setup: Initially I routed the current to be measured (70V PSU connected to a 68k resistor ...because it was just lying around on my desk...) connected to a single current channel (first and second screenshot), and connected in series to all four current channels (third screenshot).  I initially configured the acquisition system to scan alternatingly the current channel and a voltage channel (either on the same module or on a different one, this wouldn't make any difference). For the second configuration, I scanned the four current channels in sequence, then a digital port (that isn't related to the DMM module at all) and finally a voltage channel. This scheme relates to the third screenshot.

Findings: With only the first current channel connected, I didn't find any problems or interruptions of the current flow, whatsoever. Some ringing could be observed (probably when the DMM is disconnected and reconnected from/to the current measurement multiplexer) and the voltage drop across the shunt (100mOhm @ 2mA range) is present during the current measurement. The modified setup revealed more interesting details: While switching between the current channels, everything's fine again (some ringing present but it decays in a few hundred nanoseconds, and some picked-up noise due to the unshielded wires). But after current channel 4 had been read and the instrument reconfigures to voltage measurement, I get a clamped glitch (with some contact bounce) of 400µs.

My interpretation is the following: The multiplexer card is working correctly but the input configuration relay on the DMM changes state too quickly. There should be introduced a small pause before the DMM is reconfigured after measuring currents. Unfortunately, at least from the panel of the instrument itself, it's not possible to insert a "slot" with a "pause" in the acquisition list that just disconnects the current inputs (and hence shorts them) so only in the next step, the input of the DMM will be reconfigured. If this is possible via the "UltraAcquire" software, I didn't check. One possible and simple solution in case not all current measurement channels are in use would be to "dummy"scan an unused channel before changing over to voltage measurement mode. I also found that the current measurement channels appear to be clamped via two silicon junctions in series (shorted bridge rectifier?) so the voltage drop, even if the switching sequence is troublesome/faulty, should never exceed 1.4 volts. If this is a problem for the external circuitry depends on the particular configuration. Evaluating 4~20mA sensors should be okay.

Cheers -
Title: Re: RIGOL Support fading out ? What is your experience ?
Post by: Wolfgang on September 27, 2018, 09:58:57 am
Thanks a lot for your tests. They look very plausible to me. Its a timing problem, but I found no way to adjust this using the M300 itself.

The latest state of affairs is that they took the current measurement card back, they sold me an M302 package for a reduced price, and they paid for a measurement shunt I bought from SEFRAM. So, it works now, but I dont have the combined card anymore so I can try out things.

After saying that they had no resources to attack this problem, they (RIGOL Germany) now said that they will follow up this eventually, but with low priority.

I (did not try this yet) foresee another problem with the current channels: If they are in autorange mode, the DMM must try high currents first and then step down to the lower current ranges. All this should be done with the current channel never opened, but always bridged out while the range switching occurs.