Keysight's new 34465A (6.5 digit) and 34470A (7.5 digit) bench multimeters

[dadler]

Just tried this- it works on screen, but it clicks the relays every couple of seconds and locks up the display for each update. Anyone else seeing this?

Yes, it is the same annoying relay action on the 34470A
Interestingly the much older 34410A does not do this for dual display action.

I'm new to the party here-is this new functionality across the 3446/7X range? I just can't imagine that this would be desired behavior. Imagine extended duration datalogging using up a lot of relay cycles.

OMRON G6AK-274P-STLT-US 5v

Datasheet: http://www.omron.com/ecb/products/pdf/en-g6a.pdf

Durability Mechanical: 100,000,000 operations min. (at 36,000 operations/hr)
Durability Electrical: 500,000 operations min. (at 1,800 operations/hr)

This means we can only collect measurements for 6.342 years  Not doing the math on the electrical durability.

Ok, so maybe that's a non-issue  . But the clicks and hanging display drive me batty.

[KE5FX]

Amusingly, the first thing I noticed in the new 34461A firmware is that they screwed up the "4" character in the font.  It no longer looks as if it belongs in the same character set.    You can see the effect in the shots HighVoltage posted. 

I demand a refund!  Or, um, a free 34470A upgrade, if that's easier for Keysight.

[HighVoltage]

Another no so nice surprise:

Even with the FW update, you can only use a 5k Ohm 2W and 4W thermistor for temperature measurements.
The 34410A allowed for 2.2k and 10k thermistors.
You really have to wonder, why such a simple implementation would not make it in to huge FW update.

The RTD values can be set, if needed. Just not the thermistors.

[6thimage]

Hi
Content with the new version of firmware  (34461A)
But I have a question, someone I can clarify why says Time since last calibration: 808 days ??, .......
Buy less than a month ago a representative of Keysight on Argentina

Regards

It is similar on mine - using the web interface you can find out the calibration date, which for mine is showing as "Last Calibration Date: Tuesday, January 1, 2013", despite the fact mine was calibrated on the 19th April 2013.

My guess is that the time since the last calibration requires the meter to store the date in a difference place to the cal string - so next time you get it calibrated, the time display should be correct.

[TooOldForThis]

I did some quick capacitance measurements using the 34461A's new feature compared to two other devices.

With the more instruments I get, the less know about the parts I'm measuring. 

 
Notes:   
* The 34461 initially measured a 100nF cap at 81nF but it slowly crept up to 85 over a few minutes.
** The DM3068 jumped all over the place with pF range cap.

[HighVoltage]

It is similar on mine - using the web interface you can find out the calibration date, which for mine is showing as "Last Calibration Date: Tuesday, January 1, 2013", despite the fact mine was calibrated on the 19th April 2013.

My guess is that the time since the last calibration requires the meter to store the date in a difference place to the cal string - so next time you get it calibrated, the time display should be correct.

My  34461A also shows 809 days and that might be right.
The 34470A shows 27 days since last calibration.

[HighVoltage]

I did some quick capacitance measurements using the 34461A's new feature compared to two other devices.

With the more instruments I get, the less know about the parts I'm measuring. 

 
Notes:   
* The 34461 initially measured a 100nF cap at 81nF but it slowly crept up to 85 over a few minutes.
** The DM3068 jumped all over the place with pF range cap.

The datasheet only claims 0.5% accuracy for capacitance and in the lowest readings only 1%
May be it is not meant to be a replacement for a capacitance meter and only gives us an indication

[LA7SJA]

Completely free and worth every cent if you ask me  . DC + AC is bordering useless  , but the other improvements are very good for the price and makes my 33461A even more useable. So all in all I am satisfied. Also remember that if you do not get the one you love, you just have to love the one you get.
 
Johan Fredrik.

[AndyC_772]

I did some quick capacitance measurements using the 34461A's new feature compared to two other devices.

With the more instruments I get, the less know about the parts I'm measuring. 

Just for a giggle, I tried repeating your experiment, using a cheap 100nF leaded capacitor.

Averaged over 157 samples, my 34465A quotes a mean value of 106.87nF and std dev of 0.07nF.

My Fluke 89 IV says 103.5nF.

My Fluke 289 says 106.5nF. All so far, so good.

However: my HP 4395A impedance analyser can't make head nor tail of it. The cap's amplitude and phase response above a few MHz is repeatable but complicated, making the equivalent circuit very sensitive to small measurement errors. Each time I press the button which calculates an equivalent circuit for the connected device, I get a different answer, and the answers only really agree on the cap's resonant frequency, which is about 5.42 MHz.

If I limit the analysis to 500kHz, I get C = 97.64nF, ESR = 53.6mOhm, and ESL = 13.1nH.

Not sure what the moral of the story is here, if there even is one. Probably something about measuring components under conditions which reflect how they'll actually be used. Also, a cheap 100nF leaded capacitor makes a crappy decoupler.

[dadler]

I did some quick capacitance measurements using the 34461A's new feature compared to two other devices.

With the more instruments I get, the less know about the parts I'm measuring. 

 
Notes:   
* The 34461 initially measured a 100nF cap at 81nF but it slowly crept up to 85 over a few minutes.
** The DM3068 jumped all over the place with pF range cap.

I seem to trust my DE-5000 for accurate capacitance readings over any of my various DMMs. The DER EE unit is cheap but built for the purpose. The fact that capacitance was added to the 34461a with a firmware update leads me to believe this is just an add-on, nice to have convenience feature.

[EEVblog]

DC + AC is bordering useless 

Perhaps I missed some talk on this, but why is it useless?

[rsivan]

HELLO,
on my 34461A I notice another problem: when doing continuity test ,the beep is not stable ,it flickering ,very ugly to ear ,any one same prob.?

[tautech]

DC + AC is bordering useless 

Perhaps I missed some talk on this, but why is it useless?

https://www.eevblog.com/forum/testgear/keysight's-new-34465a-(6-5-digit)-and-34470a-(7-5-digit)-bench-multimeters/msg634294/#msg634294

[6thimage]

DC + AC is bordering useless 

Perhaps I missed some talk on this, but why is it useless?

I think useless is a little too far - the locking up of the screen is a bit irritating (but then you can lock the meter up by pressing a button too soon after boot). The clicking of the relays is annoying, but how often are you going to be using both? As to the relay life, having them switching constantly will kill them quicker, but I know I will only be using both readings very occasionally, so its not really going to affect me - and I'm guessing Keysight thought it wouldn't be used very much. So the only concern for me is accidentally leaving the AC second measurements on - I would much prefer a soft button that enabled 2nd measurements for only 5 readings or so.

[dadler]

DC + AC is bordering useless 

Perhaps I missed some talk on this, but why is it useless?

Here is a video of how it behaves: https://www.dropbox.com/sc/rhipa3yvs3va7n4/AAD9qqdHhSSUO4vlQeKKYIWBa

[LA7SJA]

DC + AC is bordering useless 

Perhaps I missed some talk on this, but why is it useless?

If I prefere to take out the Fluke 287 to messure the AC component continusly then I would not us this function, meaning it is of no use to me. BORDERING useless in my opinion.
Just my 2 THB.

Johan-Fredrik

[KedasProbe]

DC + AC is bordering useless 

Perhaps I missed some talk on this, but why is it useless?

Here is a video of how it behaves: https://www.dropbox.com/sc/rhipa3yvs3va7n4/AAD9qqdHhSSUO4vlQeKKYIWBa

I would probably also find this fluctuating refresh rate to annoying to use.
Maybe for very slow changing measurement it would be ok.

[economist]

DC + AC is bordering useless 

Perhaps I missed some talk on this, but why is it useless?

Here is a video of how it behaves: https://www.dropbox.com/sc/rhipa3yvs3va7n4/AAD9qqdHhSSUO4vlQeKKYIWBa

I have a new Keithley DMM7510 and it does the same thing if you are measuring DC and have AC as a secondary measurement. The relay clicking is a little faster, however.

[dadler]

DC + AC is bordering useless 

Perhaps I missed some talk on this, but why is it useless?

Here is a video of how it behaves: https://www.dropbox.com/sc/rhipa3yvs3va7n4/AAD9qqdHhSSUO4vlQeKKYIWBa

I have a new Keithley DMM7510 and it does the same thing if you are measuring DC and have AC as a secondary measurement. The relay clicking is a little faster, however.

Hmm. Darn? I was hoping it was a bug. My Brymen BM869 and Fluke 287 seem to handle DC+AC just fine. Granted, at no where near the same accuracy/resolution. But still. Thanks for the data-point.

[economist]

Hmm. Darn? I was hoping it was a bug. My Brymen BM869 and Fluke 287 seem to handle DC+AC just fine. Granted, at no where near the same accuracy/resolution. But still. Thanks for the data-point.

I was thinking the same thing (that hand held meters with secondary display seem not to have this issue) and thought perhaps the cause was the resolution. But, turning down the resolution on the DMM7510 does not change things -- I still get that clicking relay. I also have an Agilent 34461a with the latest firmware and it is doing exactly what your 34470a is doing in the video. I agree with you that this makes secondary AC display just about useless in practice.

[6thimage]

Hmm. Darn? I was hoping it was a bug. My Brymen BM869 and Fluke 287 seem to handle DC+AC just fine. Granted, at no where near the same accuracy/resolution. But still. Thanks for the data-point.

I was thinking the same thing (that hand held meters with secondary display seem not to have this issue) and thought perhaps the cause was the resolution. But, turning down the resolution on the DMM7510 does not change things -- I still get that clicking relay.

Why would changing the resolution make any difference? The AC and DC take difference paths in the meter, those that click use a relay to change between the paths, those that don't are either using a multiplexer (to silently switch between the paths) or have two measurement circuits - I'm guessing not many, if any at all, have two measurement circuits.

So the question is why did they choose to use a relay rather than a multiplexer? Perhaps, they can achieve a better signal integrity with a relay?

With the 61A, it is an added feature, so you can't expect it not to click, considering changing from DCV to ACV on the front panel causes a relay to click. Whilst the 65A and 70A are designed so the board is common between all of the models (including the 60/61A), they could have potentially used a multiplexer instead of the relay (unless it compromises the measurements). But my guess is that they were never electronically designed for dual measurements (AC/DC wise), but they wanted to add it into the firmware as an extra feature, with the hope that it might be useful.

I think, in their minds at least, if you need to measure both AC and DC constantly, you will have two multimeters set up.

[economist]

Here is a quick video of the switching on the Keithley DMM7510. The source is 1V output from a Rigol DP832.

https://vimeo.com/user20472841/review/123033131/1f78e82b29

[dadler]

Hmm. Darn? I was hoping it was a bug. My Brymen BM869 and Fluke 287 seem to handle DC+AC just fine. Granted, at no where near the same accuracy/resolution. But still. Thanks for the data-point.

I was thinking the same thing (that hand held meters with secondary display seem not to have this issue) and thought perhaps the cause was the resolution. But, turning down the resolution on the DMM7510 does not change things -- I still get that clicking relay.

Why would changing the resolution make any difference? The AC and DC take difference paths in the meter, those that click use a relay to change between the paths, those that don't are either using a multiplexer (to silently switch between the paths) or have two measurement circuits - I'm guessing not many, if any at all, have two measurement circuits.

So the question is why did they choose to use a relay rather than a multiplexer? Perhaps, they can achieve a better signal integrity with a relay?

With the 61A, it is an added feature, so you can't expect it not to click, considering changing from DCV to ACV on the front panel causes a relay to click. Whilst the 65A and 70A are designed so the board is common between all of the models (including the 60/61A), they could have potentially used a multiplexer instead of the relay (unless it compromises the measurements). But my guess is that they were never electronically designed for dual measurements (AC/DC wise), but they wanted to add it into the firmware as an extra feature, with the hope that it might be useful.

I think, in their minds at least, if you need to measure both AC and DC constantly, you will have two multimeters set up.

But changing from DC to AC, at least on the 34465a, does not cause any relay click.

[HighVoltage]

But changing from DC to AC, at least on the 34465a, does not cause any relay click.

On the 34470A and the 34401A a relay clicks, when switching between AC and DC measurements.

[6thimage]

But changing from DC to AC, at least on the 34465a, does not cause any relay click.

I have been told (in the last hour or so) otherwise - I'm not sure if the relay will click when the meter is in its stopped mode (i.e. not taking measurements), I think it probably would, but it might be a reason why you are not hearing it.