EEVblog #933 - Keysight U1272A EMC Issue

[TheAmmoniacal]

Keysight 

[HighVoltage]

Very impressive Keysight!
And finishing ahead of schedule!

Thanks again and Happy New Year to Keysight!

[bernroth]

Thank you Keysight for your message and for keeping us updated in this forum! This is really appreciated!

I'm very curious about the actual modifications which have been done to the input section to solve the EMI issues.

Gesendet von meinem Nexus 5 mit Tapatalk

[Barny]

Happy new year and a big thank you to all workers at Keysight.

[TheAmmoniacal]

Just received my U1282A -- Thank you very much Keysight. Definitely a company worth supporting.

I do have on criticism about the meter though, the test leads / probes that comes with it suck. I'm surprised nobody else have commented on this, or am I just being unreasonable? They both look and feel like a pair of $2 ones that you get with a Vichy meter, they are not silicone, they are stiff, not very sharp and have plastic mold artifacts several places. They are in fact comparable with these https://www.aliexpress.com/item/2pcs-1lot-Digital-Multimeter-Universal-1000V-20A-Test-Lead-Probe-Cable-SMD-SMT-Needle-Tip/32542512788.html -- at $1.75 a pair!

Way below expectations for a meter of this caliber, and I most likely won't use them at all. It seems like even Keysight has a lot to learn from the underdogs like Brymen. 

[bitseeker]

The leads that came with my U1252B are similar (leads are a bit stiff, tips not very sharp), but the tips are shrouded. Granted, they're not up to the level of the ProbeMaster probes (silicone, super-sharp tips, retractable-shrouded banana plugs) on my bench meters.

[HighVoltage]

Way below expectations for a meter of this caliber, and I most likely won't use them at all. It seems like even Keysight has a lot to learn from the underdogs like Brymen.

I noticed this too but I never really use the supplied stiff cables anyways. I have a bin full of supplied stiff cables and even some Fluke handheld meters came with such bad quality cables that I just have given up on it.

The U1282A meter on the other hand is very good and I like it a lot.

[saturation]

I received my unit via Fedex late Dec 2016 but haven't returned to see it, but thanks Keysight.  Will feedback when I do.

[Zbig]

@Keysight Technologies Rep: those are great news, thank you! BTW, I can see you guys have put an official Service Note regarding this issue in the product support area for U1270 series of your website, but the actual PDF documents are AWOL (Error 404).

EDIT: It's fixed now.

[Zbig]

Got an USB-IR cable without any explicit prior shipping confirmation e-mail early December. And just now got an e-mail confirming the shipment of the cable. Either they forgot to send cable shipping confirmation back then and decided it's better late than never or sent me another cable by mistake or were going to say they've shipped the redesigned 1270 meter but said IR cable instead...

[Faith]

Today we are pleased to announce that we have completed a redesign of U1270 multimeters ahead of schedule

Same part number? Is there any way to identify the new versus the old one other than the date of which it was manufactured?

[bitseeker]

Today we are pleased to announce that we have completed a redesign of U1270 multimeters ahead of schedule

Same part number? Is there any way to identify the new versus the old one other than the date of which it was manufactured?

Don't know. The first four digits of the serial number will surely be different. Maybe the model designation will have a 'B' instead of an 'A'.

[Berni]

I have just received my new U1281A today. Didn't get any email telling me it shipped, just suddenly shown up, quite a pleasant surprise. Thanks Keysight!

After having a bit of a play around with it i think the U1273A does a lot of things better, but that continuity buzzer on the U1281A is simply awesome. I know its lame to get exited over a simple buzzer but its the first multimeter i used that had a latching one but was still super quick.

Im also surprised how much bigger it looks compared to the U127x series, yet putting them side by side shows they are almost the same size, must be something about its case design that makes it look so huge.

[Sbampato12]

I've received my U1282A last Thursday. I'm a little busy lately, so I didn't wrote before.

Didn't get any email, and this time I didn't had to pay anything (great).

Like Berni said, the continuity buzzer is really quick. But the DMM is not so fast. I think I prefer the U1272, but it has more functions... I need some more time to use and build a taste a little better.

The big display is a really good thing.

The probes that comes with it looks good, but the red one arrived a little bended at botton (where the cables get out), and the readings are floating all around, with another one, it is a rock solid. I guess I not so luck with KS probes (I bought a U1194 that came with bended probe tip, I don't remember what color, and KS replaced it with a new pair, very quick. This time I don't think I need a replacement, I'm already very happy with the DMM replacement   )

Thank you Keysight!

[bernroth]

I am a bit late as well. The U1282A arrived when I was on vacation in December.

Thank you Evelynn & Keysight for the replacement!  Great service

The U1282A is a beast compared to the U1272A but it's very well made and it performs great.
The leads are not perfect but much better than the wobbly ones which have been delivered with my Fluke 85V.

When doing the EMC test with the RFID reader, I notice a very low mA reading which is totally acceptable.
No big readings or spooky effects
All the other readings are fine although I have the impression that the readings take more time to get properly displayed.

Continuity does not flash the display backlight but toggle the VSense LED starting with FW 1.03

BTW VSense:
I did not notice a big influence on the VSense alert when being near to a RF source (like RFID reader).
Anyhow, VSense does not work very well IMHO, even in HI mode. I need to do further testings.

I am used to Flukes Volt Alert function in the 117 meter which is very sensitive. You can easily check for mains wiring in the wall before drilling.


When switching the meter on, it shows firmware version 1.05 whereas on the product page only the older firmware 1.04 is downloadable.

@Keysight: What has been changed in 1.05 compared to 1.04?
Please update the download page and the Changelog at http://www.keysight.com/upload/cmc_upload/All/U1281_82_firmware_release_note.txt

[Zbig]

Anyone got their redesigned U127x yet? It's two weeks after the announcement, I'd think they should start arriving already...

[saturation]

Finally got to play with it.  Compared to the 87V and 1272a briefly:

1282a is more work-a-like a Fluke 87V but with far better and updated features and true toughness.  The LCD has higher contrast than 1272a making it easier to see in ambient light, not that its also bigger but contrast is as good as the 87V, on the 1272a I often had to turn on backlight to improve the contrast.  While rotary switch torque is much higher, its not recessed like the 87V, its less likely to be turned on accidentally.

The meter is faster and more accurate.

I was getting slow or unstable readings originally OOB, compared to the 87V and 1272a.  A lead switch showed the results was from the Keysight probes, switching to the Fluke probes fixed the problem.  Cleaning the Keysight probe tips with IPA solved the issue, it had some barely noticeable coating.

[wraper]

The meter is faster

I noticed exactly opposite.

[saturation]

I had the same issue, it was noticeably slow until I switched probes, then cleaned the factory leads as in my prior post.  Try it and report back.

The meter is faster

I noticed exactly opposite.

[Muttley Snickers]

I have already written over a full page of notes and had intentions of starting a dedicated thread for the U1280 series but haven’t gotten around to it as yet, mine is definitely slower than the U1272A and takes some time before settling and I even referred back to the manuals when it first arrived to verify, from memory the U1272A updates at 7 times a second whereas the U1282A is either 5 or 40, setting it to 40 in the menu will drop the meters count down to a super fast 6600 instead of the regular 66000.

My new U1282A meter is also prone to fluctuation when doing resistance testing and placing my hand in close proximity to the meter, I only found this out last night whilst documenting comparative measurements in different ranges and it requires further testing today to confirm, also I posted this chart below in the supporters lounge and forgot all about those who may not have access, the chart should be completed later today with the min-max and some other notes to be added, some may find it a handy initial reference for the U1280 series.     

[saturation]

Thanks Muttley, hopefully you publish you list of issues so we can confirm them.  If you have more than 2 units, its not firmware dependent then?

I have already written over a full page of notes and had intentions of starting a dedicated thread for the U1280 series but haven’t gotten around to it as yet, mine is definitely slower than the U1272A and takes some time before settling and I even referred back to the manuals when it first arrived to verify, from memory the U1272A updates at 7 times a second whereas the U1282A is either 5 or 40, setting it to 40 in the menu will drop the meters count down to a super fast 6600 instead of the regular 66000.

My new U1282A meter is also prone to fluctuation when doing resistance testing and placing my hand in close proximity to the meter, I only found this out last night whilst documenting comparative measurements in different ranges and it requires further testing today to confirm, also I posted this chart below in the supporters lounge and forgot all about those who may not have access, the chart should be completed later today with the min-max and some other notes to be added, some may find it a handy initial reference for the U1280 series.     

[Tom45]

Look what arrived yesterday:






Seems to be the same meter with no indication of a rev. from the original. Agilent to Keysight notwithstanding.






If I get time I'll do the EMC test and report back.

[TheAmmoniacal]

Looks great, the U1272A remains my favorite DMM! (over the U1282A!)

Can you also check if the continuity buzzer is faster on this revised meter? (or did they only fix the EMC issue?)

[Tom45]

The EMC problem is definitely fixed. With a single lead connected to the 10 A input my old meter shows -25 amps with a 10 vpp 10 MHz square wave. The new meter is 0.0000 amps no matter what I tried.

When I tried feeding the square wave to both meters at the same time, the new meter's filter seems to affect the reading of the old meter, dropping it from -25 amps to -7 amps. As a control I fed the square wave to the old U1272a and the eevBlog Brymen. The U1272a reading dropped a bit from -25 to -18.

The continuity tone has the same leisurely pace as the old one. Both old and new backlight flashes are equally quick for continuity checks.

[Faith]

Look what arrived yesterday

Thank you for the update Tom!~ Looks like I'll just have to tell my reseller to make sure I get one fresh from Keysight's oven