Just bought a 'used' Agilent U1242B Meter from Keysight on eBay

[Gandalf_Sr]

Excellent, I am glad you got the DMM early. 

I presume you are feeding a 5V reference voltage in your picture, so a 0.04 error is well within spec, very good for a handheld DMM with a 6000 count resolution, it is a great buy.

Thanks

Among other stuff, I have a Keysight 34461A that was bought new in Dec 2015 (not calibrated since but thinking about it) and a DP832A that was bought in Mar 2018; I used the 34461A to 'calibrate' the DP832A soon after I got it.  The DP832A was set to 5V out and the 34461A was reading 5.00182 connected in parallel with the U1242B.

I've got a DMMCheck Plus on its way to me in the mail so more accurate tests will soon be possible.

[Gandalf_Sr]

I figured out how the U1117A Bluetooth Adapter is supposed to attach to the U1242B meter, it needs a U1179A plastic bracket which I just ordered from Amazon for $12.  It's a kind of kludge in that the plastic bracket fits into the squidgy test-lead holders on the back.  I was thinking of designing one in FreeCAD and then 3D printing but it's not worth my time and effort.

[NoisyBoy]

Among other stuff, I have a Keysight 34461A that was bought new in Dec 2015 (not calibrated since but thinking about it) and a DP832A that was bought in Mar 2018; I used the 34461A to 'calibrate' the DP832A soon after I got it.  The DP832A was set to 5V out and the 34461A was reading 5.00182 connected in parallel with the U1242B.

I've got a DMMCheck Plus on its way to me in the mail so more accurate tests will soon be possible.

Good to hear, I have a few 34461A and 34401A in my hobby lab as well, they all go back to Keysight for annual cal and adjustment.  For a new DMM like 34461A, I can see the drift (though small, often in the last 2 digits, always still within spec) in the first couple years of use in their report.  They settle down over time, the drift on my 10 years old 34401a is minimal, so the annual cal is mostly just for peace of mind for the older gear.  So if your 34461A has never gone back for cal after 4 years, the DMMCheck would be a great tool to do a sanity check on the last couple digits.  I was very tempted to get one, but with the annual cal and cross check I can do across various DMMs, I am still on the fence for it.  Let me know how you like it.

[Gandalf_Sr]

@NoisyBoy
Thanks, I'll let you know what the meters read from my DMMCheck once it gets here. Just out of interest, what is the cost of a Cal for the 34461A?

[NoisyBoy]

It varies by the certification level you need, it starts at $240 and goes up to $458 with guardbanding.  I only use the basic cal since it is just a hobby lab. 

[Gandalf_Sr]

$245 seems pretty reasonable.

[NoisyBoy]

I thought so, there are cheaper alternatives out there for 6.5 digit DMMs.  But many cannot handle the 34461A, however they can do 34401A NIST traceable cal for around $100.

Despite the higher cost, I personally thought all my interactions with Keysight, whether it be will new equipment sales, parts, repair or cal to be truly exceptional.  I have never encountered anyone who is not friendly and top tier professionals.  I can have everything billed on one account, they are super easy to do business with.

[Gandalf_Sr]

Well my DMMcheck Plus arrived and I did a quick test on some of my meters.  My U1252B is really good and my 34461A reads 5.00001 Volts when the DMMcheckpus cal sheet says 5.0000 Volts; rats! That's only 0.0002% accurate /s

[NoisyBoy]

Excellent, you are probably in the clear.

One thing to be aware of its behavior at different voltage range, it is the biggest limitation for DMM checkers (and frankly, that's why I have not bought the DMM Check+).  As 34461A has a separate gain correction for each of the 5 ranges in DC, and 11 performance verification checkpoints in DC alone.  It is complex enough that I have considered buying a Fluke 5720A at some point.

My 344461A is back at Keysight Rossville for cal as we speak.  While it was within tolerance for up to 10V DC, they found it to be out of tolerance in DC (not sure what voltage range, I will find out after I get the report back). 

I may need to get over my accuracy OCD someday and spend some of the annual cal budget in more new test gears   Challenge is Keysight is so easy (and a pleasure) to do business with, which makes breaking the habit hard.  They come and pick up my gears with their equipment van, do the cal, and return the equipment to me.  Everything is billed to my account, I liken it to having a tap at the bar   

But it gives me 100% confidence in my test gears when I need to use them, so I suppose it is still a small price to pay to keep the OCD at bay.

[Gandalf_Sr]

You're right; I should just send it in to Keysight for Cal, it's my best meter and I paid $1,000 for it 4 years ago.

Unless you have a waaaay better meter than mine (the 344461A eh?), you may want to send your keyboard in for Cal too 

[NoisyBoy]

You still on the old gear?  You really need to upgrade to the KKeysight 344461A, I am waiting for the even newer 3444461A, it is coming out any day now 

This reminds me of the TI calculator from the 70's, I had a TI 30, the key bounces all the time creating double/triple digit entries, terrible defect in a calculator.  Their higher end models were much better, but none came close to a HP with RPN.

Back on topic, the recommended cal period is 1 year, with a max of 2 year per recommendation from Keysight.  So I would say a cal for your best meter may be a good investment, you can use it as a transfer standard for your other meters across all voltage ranges and measurements.  It minimize the curse of multiple versions of truth when you own multiple DMMs.  Back in the old days, I had one analog meter, I never questioned its reading.  The arrival of my second meter was perhaps the beginning of my OCD.

As the meter ages, the drift reduces, as evident in my two almost 10 years old 34401As, those are rock solid meters and a joy to use.  But for a new meter, a cal after a few years of use, though may not be necessary, could be a nice treat for yourself.

[rsjsouza]

You still on the old gear?  You really need to upgrade to the KKeysight 344461A, I am waiting for the even newer 3444461A, it is coming out any day now 

This reminds me of the TI calculator from the 70's, I had a TI 30, the key bounces all the time creating double/triple digit entries, terrible defect in a calculator.  Their higher end models were much better, but none came close to a HP with RPN.

Funny how you mentioned that issue with the TI-30 calculator; it seems your keyboard is doing the same... 

As for the calculator itself, mine started doing this when the batteries dropped below 7.5V or whereabouts. Brownout protection circuitry didn't exist at the time.

[2N3055]

If you look at a curve of how they settle, for home or non formal work, good practice is after you buy new, calibrate  after 1, than wait for 2 then 3 and then 5 years... After 11 years they are pretty much flat afterwards...
If you need it for work, you will calibrate to satisfy paperwork..  Some people keep it at 3 months intervals to be able to use 90 days specs..

[Gandalf_Sr]

Do you think there will be any pushback from Keysight if I send my 34461A in for it's first Cal at 4 years old?

[2N3055]

Do you think there will be any pushback from Keysight if I send my 34461A in for it's first Cal at 4 years old?

Why? What do they care.. But there is a big chance that it will need adjustment if it was never adjusted since bought..
And most likely it will be quite stable from now on..

[NoisyBoy]

Do you think there will be any pushback from Keysight if I send my 34461A in for it's first Cal at 4 years old?

Why? What do they care.. But there is a big chance that it will need adjustment if it was never adjusted since bought..
And most likely it will be quite stable from now on..

No, they don't care.  Call them and they will give you a quote, you will then call back and give them your credit card number (or have them bill it to your account if you have one).  The cal is $240, plus $35 on return shipping.  You will have to make arrangement to get the meter to their cal lab, so the original shipping box and foam would come in handy if you plan to UPS or Fedex it.  If you live close to one of their service center, they can pick it up from your home and do all the packing for you if it needs to be send out (they take responsibility for any damages, you just give them the bare meter without cable or probes), or they will do the cal at the local lab.   If you have over $300 of services, the courier service is free, otherwise it is $100.  I usually batch all my Agilent/Keysight gears into groups for cal, so I can get the free courier service. 

[Gandalf_Sr]

Thanks guys.  Does 'adjustment', if needed, cost more than a straight Cal or is it all part of the $240?

[NoisyBoy]

This is what's included in the basic cal (the lowest tier):

• Tests all product specifications using manufacturer-developed procedures and software
  Includes certificate and full measurement report
  Includes all adjustments and as-received data for any out-of-tolerance instrument
  Complies with ISO 9001:2008

[Gandalf_Sr]

Sorry to be a pain but, what's the difference between...
Keysight Calibration Agreement $228 and
Keysight Calibration Per Incident $240?

I tried to look it up but it's as clear as mud.

[NoisyBoy]

I never got quoted that price.  I believe that was for people with annual cal service over $10,000, I could be wrong though. 

[Gandalf_Sr]

You're probably right, that would make most sense.  When I mouse-click the little (?) bubbles to the left of each item, the exact same pop-up text comes up with the 5 bullets the service includes...

- Tests all product specifications using manufacturer-developed procedures and software
- Includes certificate and full measurement report
- Includes all adjustments and as-received data for any out-of-tolerance instrument
- Complies with ISO 9001:2008
- Displayed price is total for one calibration

I guess I'll have to call them on Monday and check unless Daniel is around and can clarify?

[Gandalf_Sr]

Hey, look what I found on eBay!

[EDIT] Is no one going to bite?

[Keysight DanielBogdanoff]

@Gandalf_Sr - I have no clue what the difference is! I'm sure the work is the same, but it probably has something to do with the way service contracts get setup, especially for enterprise folks.

[NoisyBoy]

Ah, I see the seller much have also read about the upcoming KKeysight 3444461A and try to sell his 344461A before the announcement.

My meter just finished its spa treatment at Keysight Roseville and it should be on its way back to me soon.  It passed all tests except one test point: -100V DC, it is just slightly out of the spec by 0.00013%.  Everything is now back in spec and good for another year or two.

DC alone, there are 11 separate cal points, and AC has 20 cal points.  When you consider all the other functions that needs to be calibrated/adjusted, the price Keysight charge is very reasonable.  As it will take many hundred cals to justify owning my own Fluke 5730A 

Daniel, thanks for another superb Keysight experience.

[Gandalf_Sr]

Guys, I set up a service agreement with Keysight today for $228.  It's VERY unclear but that agreement allows me to send the covered meter (the 34461A in my case) in at any time in the year for calibration which I've requested to happen immediately. Apparently this save me money as I only pay for the shipping to their nearest service center.