Shahriar Rigol DM3058 and Keysight 34465

[Echo88]

Hmm, any good DMM >= 5.5 DMM (HP, Fluke, Keithley) can be calibrated everywhere with the right calibrators. When Rigol states that the DMM can only be calibrated by Rigol, then they
1. didnt bother to implement a simple calibration routine  or
2. want to get more money through calibrations.

Either way: enjoy your missing freedom, but hey, its cheap right. 

[2N3055]

Of course it can be calibrated and verified at any facility that can calibrate other instruments ot that accuracy..
There is a Service manual with clear instructions how to perform instrument performance verification.

The fact that you cannot adjust it except in Rigol is annoying. You also have to send it to them for service. No third party service exist that I know of.

Why they do it, I don't know. It might be to monopolize service income, or something else. It might even be that they want to gather service and calibration statistics.. HP ran it's calibration service both as income source but also as a way to gather statistical info on devices and their real (not estimated) stability, drift etc...  They use that data all the time, they even use it to prolong calibration intervals on some equipment ...
Maybe Rigol decided to start gathering such data ... Who knows.

All I know I have to send it somewhere anyways, and Rigol quote to do it was actually very good. So I might as well send it to Rigol.

Regards,
Sinisa

[EEVblog]

Hmm, any good DMM >= 5.5 DMM (HP, Fluke, Keithley) can be calibrated everywhere with the right calibrators.

Do not confuse "calibration check" with "calibration adjustment".
Any good calibration house will NOT calibration "adjust" your instrument unless you specifically ask and pay for that.
When you send your meter off for "calibration" it is is only "checked", not adjusted.

[Echo88]

I meant adjusting, sorry if i didnt make that clear in my post.

[saturnin]

Of course it can be calibrated and verified at any facility that can calibrate other instruments ot that accuracy..
There is a Service manual with clear instructions how to perform instrument performance verification.

The fact that you cannot adjust it except in Rigol is annoying. You also have to send it to them for service. No third party service exist that I know of.

Well, I can send a Rigol meter to a cal lab where they may find out it is out of specs. Then, I have to send it to Rigol to adjust it. I would not call it annoying I would call it fail, because such procedure would cost definitely more money. All reputable T&M manufactures allow third-party adjustment of their 6.5 digit multimeters...

Obviously, Rigol is able to implement user calibration - DM3058 series supports it: http://beyondmeasure.rigoltech.com/acton/attachment/1579/f-059c/1/-/-/-/-/DM3058%20Calibration%20Guide.pdf, so I only wonder why they didn't not implement it in DM3068 series too.

[2N3055]

@saturnin  (by the way, "Saturnin"  by Zden?k Jirotka is my favorite book :-)

As always with calibration, we have a terminology problem as well as freedom / economy problem ...

End user 99.999 % of the time cannot make adjustments of 6.5 digit meters that will not make it worse than it was.
Third party accredited labs can.  Fact that Rigol didn't publish adjustment procedure publicly is annoying. It impedes my freedom. I don't like it.

But instruments like DM3068 don't go out of calibration that easy.. Adjustments are only needed after many years (if any) or after damage/repair. Some users don't want meters to adjusted at all.. THey just send them on regular calibration checks, keep history, and mathematically correct measurement results..
In case of repair, where would you send your Keysight meter? I would send it to Keysight  anyways.. In Croatia we have a proverb: " If it cries, give a child to it's mother.. She'll know what to do.." It is usually a good advice..

I would have huge problem if Rigol would monopolize things and then tried to charge me 1000€ for calibration check... But they don't, prices I was sent were very good.
So while in theory, my freedom of choice is taken away from me, in practice I couldn't care less...Freedom of choice in business is all about not paying too much and power to negotiate for a good price for the service or product you need...
If price is OK in the first place no need to negotiate... Actually, I really don't like to haggle with salesmen...

Situation is what it is, right now. It is not ideal, but acceptable. If that changes to worse, i will deal with it accordingly.. But I don't think they will worsen their customer support. If anything, Rigol, Siglent and other Chinese  manufacturers are demonstrating they are learning very, very fast...

As a side note, I will be sending my DM3068 for a ISO calibration at Rigol in months to come, and will document the experience and share it with forum, from customer experience, process,  to results and documentation. 
I'm also curious how will it go, I guess we will find out.

Regards,

Sinisa

[saturnin]

@saturnin  (by the way, "Saturnin"  by Zden?k Jirotka is my favorite book :-)

Good to hear the book found its fans abroad too.  So, would you ever start "a doughnut fight" in a café? 

Back to the topic... I don't think it is so rare a multimeter needs adjustments after several years of service. 6.5 digit multimeters have quite tight specs and especially HV DCV and OHM ranges can drift out of them.

I don't know situation in your country, but here cal labs are accessible. I have two in close neighborhood (I don't live in a big city though). Both are well equipped (Fluke 8508A, Fluke 5720A, Datron 4708). I prefer to deliver my instruments personally to save shipping costs and to avoid a possible damage during transport by a courier.  That's why I don't like Rigol's decision not to allow third-party adjustment of some of their instruments...

[3roomlab]

@saturnin  (by the way, "Saturnin"  by Zden?k Jirotka is my favorite book :-)

i was reading the thread, and now i go to look for saturnin by zden ... and found it on youtube

i think rigol is not shy about their "copies". 2N3055 i think is quite right about monopoly, i think many (too many) chinese "copy" companies made alot of money using "copies". when they got rich enough, they eventually buy over the original company they copy from (you guys hear these stories before yes?). i guess the only way to know the difference, is for someone to post actual data about long term accuracy differences. which means, they probably should join some kind of hobby "calibration club" to economically obtain some form of knowledge about their accuracy drifts?

but since HO posted his drift findings, if we take it as it is. 35ppm drift per year for a cheapy DMM? i think is worse than used K2000?

it would be interesting if shahriar himself post some data about his rigol

[2N3055]

@saturnin, I'm not much of a "doughnut fight" guy, but I might have a spare binocular if you ever lose one while looking into water well... Cause, you know, that sort of thing happens all the time... :-) Also if you want to become shark hunter, maybe something can be arranged..
But in all honesty, as I'm getting older, I would be more of a Doctor Vlach type..

I'm glad that you have calibration labs so available, and now understand your frustration. I would be too if I was in your situation. God, I wish I was in your situation...
Unfortunately, my nearest lab is in Zagreb, and that is not so close for me. And after entering EU, it is almost the same price to ship it to Zagreb as it is to Rigol Germany, or some other calibration lab..

I do agree that after some years you would need adjustments. My practice is to send new instrument after cca 2 years for full cal with adjustment.  That will take care of most of accelerated initial drift. So adjusted instrument is quite ok to be sent only for performance verification afterwards for some years to come..  And then you can see how it drifts and plan to send it for adjustment when needed.
Of course, it depends on quality of instrument, environment etc etc..

Take care!!

Sinisa

[2N3055]

@saturnin  (by the way, "Saturnin"  by Zden?k Jirotka is my favorite book :-)

i was reading the thread, and now i go to look for saturnin by zden ...

Search for Zdenek Jirotka, "Saturnin".. It is good fun...