Fluke 5100B Calibration

[tom99]

Hello, I am new the forum and hope I can post this here.

I have a Fluke 5100B which I picked up for £77 from eBay (Non-functioning). Anyway, pretty much all fixed now after many hours. Now I am hoping to have it calibrated, only for my home lab setup. But no one near me can offer calibration for these sorts of devices. I am wondering if anyone in England (ideally south) has had one of these or similar units calibrated and could provide some company names? Or have people calibrated these themselves? I don't have all the equipment to do that and my test equipment hasn't been calibrated in some time so I doubt that would even be worthwhile. I appreciate any advice or comments.

Thanks, Tom

[Ugur]

Hello,

Fluke UK calibration lab provides calibration service for this instrument.
service.uk@fluke.com

[tggzzz]

Welcome to the forum, and congratulations on your repair

Not knowing anything about you or your background or experience, I'll obliquely mention traps that some people fall into....
Do you want it calibrated or adjusted? 
Do you want to know its output is within specification, or to have its output measured with stated uncertainties?
How deep are your pockets?

[tom99]

Thank you - I did try Fluke but no reply from them on a price and I expect it would be expensive.

I wanted a full cal, not just adjusted. It will then be used to calibrate some of my other equipment. Unfortunately I have a HP meter to calibrate too but the 5100B isn't precise enough... So will look at getting that sent out for cal somewhere too.

[tggzzz]

Be aware of Keysight (i.e. HP) policy, as per https://www.eevblog.com/forum/testgear/keysight-officially-lost-the-plot-dont-buy-if-youre-a-hobbyist/

It feels like you might not be using the terms "calibration" and "adjustment" in the way used in metrology.

Can I suggest you do some research on "calibration vs adjustment". For example https://blog.wika.com/knowhow/calibration-or-adjustment-wheres-the-difference/ contains

To “calibrate” in measurement technology means to determine the measuring deviations in the complete measuring instrument. With calibration there is no technical intervention at the measuring instrument, such as zero adjustment, span and linearity setting, etc. With indicating measuring instruments calibration establishes the measuring deviation between the display and what is claimed to be the correct value of the measurand.
...
“Adjustment” means setting or alignment of a measuring instrument (also a material measure) so that the measuring deviations are made as small as possible or that the magnitudes of the measuring deviations do not exceed the error limits.

If I was going to be seriously calibrating my equipment, I'd be very careful about what any given company might mean by "full calibration". Or "calibration" for that matter

[bdunham7]

It feels like you might not be using the terms "calibration" and "adjustment" in the way used in metrology.

The 5100B really isn't 'metrology', although I realize that is the title of this forum.  In the interest of clarity and perhaps to avoid being called a pedant, I would suggest using the terms that are found in the Fluke manual.  These would be 'performance check' and 'calibration' IIRC.  The procedures for 'calibration' on the Fluke 5100B involve a lot more than just metrological concerns, it is a complete service adjustment.  Not that any of that happens in a cheapo 'calibration' from whoever.

[bdunham7]

Now I am hoping to have it calibrated, only for my home lab setup. But no one near me can offer calibration for these sorts of devices.

I have two of these, congratulations on actually getting yours working.  If you do not need actual paperwork for your use, then I'll point out that the cost of a proper calibration for one of these will probably exceed the price of a good 6.5 digit DMM and than it is only good for six months--or less if the 5100B breaks or drifts, which they do.  A typical good 6.5 digit DMM is probably pretty close to good enough to meet the specs for calibrating the 5100B all on its own.  The only issues I can think of that you might have are the low current ranges and AC accuracy on some ranges. The 5100B has surprisingly good AC specs considering it was intended for 4.5-digit or less meters.  But a Keithley DMM6500 would probably give you a pretty decent result.

The calibration procedure is quite involved and a lot of it goes into making sure the internal modules are functioning correctly, not just trimming the outputs.  The low-cost calibration providers are not likely to do any of that stuff, and from what I've seen they typically use improper test points that are much easier to get a pass on from this unit.  So either acquire a friend with a 6.5/7.5/8.5 digit DMM or DIY.

[Pip]

It feels like you might not be using the terms "calibration" and "adjustment" in the way used in metrology.

The 5100B really isn't 'metrology', although I realize that is the title of this forum.  In the interest of clarity and perhaps to avoid being called a pedant, I would suggest using the terms that are found in the Fluke manual.  These would be 'performance check' and 'calibration' IIRC.  The procedures for 'calibration' on the Fluke 5100B involve a lot more than just metrological concerns, it is a complete service adjustment.  Not that any of that happens in a cheapo 'calibration' from whoever.

The 5100B certainly is considered to be part of 'metrology'. It was once a very important link in the traceability chain of electrical instrument calibration labs. We retired ours shortly after the purchase of our first 5700A in 1995.

Just for clarification, when Fluke says 'Performance Test' they mean 'calibration verification', and 'Calibration Procedure' means 'adjustment procedure'.

[bdunham7]

The 5100B certainly is considered to be part of 'metrology'. It was once a very important link in the traceability chain of electrical instrument calibration labs.

You can define 'metrology' however you like, but I'd limit the term to the top-tiers of measurement science and accuracy.  The 5100B is a convenient multifunction calibrator for calibrating moderate quality DMMs.  It is not a standard of any sort.  The only traceability link it provided was that between the actual metrology-grade standards used to calibrate it and the pedestrian-quality meters that were calibrated by it. 

Just for clarification, when Fluke says 'Performance Test' they mean 'calibration verification', and 'Calibration Procedure' means 'adjustment procedure'.

How does that clarify anything?  By 'performance test' they mean the steps that are listed under Performance Test in the manual and by 'calibration' they, again, mean the steps they have listed.  I don't know why it has become fashionable to insist that the term 'calibration' for DMMs and multifunction calibrators must mean the same thing as it would for a resistance or voltage standard.  Sort of a 'foolish consistencies' thing if you ask me.  Or even if you don't. 

[TiN]

BIPM's VIM International Vocabulary of Metrology - Basic and general concepts and associated terms clearly states:

2.39 (6.11)
calibration operation that, under specified conditions, in a first step, establishes a relation between the quantity values with measurement uncertainties provided by measurement standards and corresponding indications with associated measurement uncertainties and, in a second step, uses this information to establish a relation for obtaining a measurement result from an indication

NOTE 1 A calibration may be expressed by a statement, calibration function, calibration diagram, calibration curve, or calibration table. In some cases, it may consist of an additive or multiplicative correction of the indication with associated measurement uncertainty.

NOTE 2 Calibration should not be confused with adjustment of a measuring system, often mistakenly called “self-calibration”, nor with verification of calibration.

And

3.11 (4.30)
adjustment of a measuring system
adjustment set of operations carried out on a measuring system so that it provides prescribed indications corresponding to given values of a quantity to be measured

NOTE 1 Types of adjustment of a measuring system include zero adjustment of a measuring system, offset adjustment, and span adjustment (sometimes called gain adjustment).

NOTE 2 Adjustment of a measuring system should not be confused with calibration, which is a prerequisite for adjustment.

NOTE 3 After an adjustment of a measuring system, the measuring system must usually be recalibrated.

What some vendors and labs may call their proprietary measurement or/and adjustment procedures, it's their own business, but to limit confusion, it's recommended to stick with accurate terminology, recognized by international bodies.

To OP, your best bet is to find someone with recently calibrated 6.5+ digit DMM in the area and bring your 5100B to get your unit tested and perhaps adjusted yourself. It's unlikely that most commercial labs would bother with 5100B, and shipping this beast back and forth probably cost multiple times more then you paid for it.

[Pip]

The 5100B certainly is considered to be part of 'metrology'. It was once a very important link in the traceability chain of electrical instrument calibration labs.

You can define 'metrology' however you like, but I'd limit the term to the top-tiers of measurement science and accuracy.  The 5100B is a convenient multifunction calibrator for calibrating moderate quality DMMs.  It is not a standard of any sort.  The only traceability link it provided was that between the actual metrology-grade standards used to calibrate it and the pedestrian-quality meters that were calibrated by it. 

Just for clarification, when Fluke says 'Performance Test' they mean 'calibration verification', and 'Calibration Procedure' means 'adjustment procedure'.

How does that clarify anything?  By 'performance test' they mean the steps that are listed under Performance Test in the manual and by 'calibration' they, again, mean the steps they have listed.  I don't know why it has become fashionable to insist that the term 'calibration' for DMMs and multifunction calibrators must mean the same thing as it would for a resistance or voltage standard.  Sort of a 'foolish consistencies' thing if you ask me.  Or even if you don't. 

You are welcome to your own limited opinion. In my opinion, metrology is more encompassing and not just limited to the top-tiers.

Calibrators in primary and secondary labs are just working standards however, for many lower-level labs, the calibrator is their reference standard.

The clarification was for tom99's benefit.

Calibration of DMMs and multifunction calibrators does mean the same thing as it does for a resistance or voltage standard. The concept hasn't changed in at least the last 30 years. What is your point?

[tom99]

Be aware of Keysight (i.e. HP) policy, as per https://www.eevblog.com/forum/testgear/keysight-officially-lost-the-plot-dont-buy-if-youre-a-hobbyist/

It feels like you might not be using the terms "calibration" and "adjustment" in the way used in metrology.

Can I suggest you do some research on "calibration vs adjustment". For example https://blog.wika.com/knowhow/calibration-or-adjustment-wheres-the-difference/ contains

To “calibrate” in measurement technology means to determine the measuring deviations in the complete measuring instrument. With calibration there is no technical intervention at the measuring instrument, such as zero adjustment, span and linearity setting, etc. With indicating measuring instruments calibration establishes the measuring deviation between the display and what is claimed to be the correct value of the measurand.
...
“Adjustment” means setting or alignment of a measuring instrument (also a material measure) so that the measuring deviations are made as small as possible or that the magnitudes of the measuring deviations do not exceed the error limits.

If I was going to be seriously calibrating my equipment, I'd be very careful about what any given company might mean by "full calibration". Or "calibration" for that matter

No I just want them calibrated. Only adjusted if needed but will run through cal first... All my equipment should be within tolerances, excluding my HP 6624A's (these may need full cal with adjustment) and HP 3458A's (which I cal using another company).

[tom99]

For anyone interested I received a quote for calibration (no adjustments) £210 with UKAS traceability - excluding shipping costs. I was a little surprised, I had expected more. Not sure what you all think, but possibly too good to be true?

[bdunham7]

Calibration of DMMs and multifunction calibrators does mean the same thing as it does for a resistance or voltage standard. The concept hasn't changed in at least the last 30 years. What is your point?

Well, again, it depends on who you ask.  But if you send your DMM into an OEM or simply read their manual, the 'calibration' offered or specified typically includes adjustment (as needed) without any further discussion.  So if I send a DMM to Fluke and select one of their calibration options, they will automatically perform any adjustments if needed.  That's just part of their standard service that they refer to as 'calibration'.  For resistance and voltage standards, the opposite is typically true.  For the very top-tier 8.5 digit DMMs the options and procedures may be different.

Calibrators in primary and secondary labs are just working standards however, for many lower-level labs, the calibrator is their reference standard.

We don't have to agree on what the terminology means as long as everyone is clear on the differences.  I wouldn't call a MFC a standard and neither does Fluke, but if you choose to, I hope it isn't a 5100B. 

[bdunham7]

For anyone interested I received a quote for calibration (no adjustments) £210 with UKAS traceability - excluding shipping costs. I was a little surprised, I had expected more. Not sure what you all think, but possibly too good to be true?

If you don't need a certificate, what value are they providing for you for that amount of money?  The way this typically works is that the end user (you) would repair and adjust everything in-house, then send it to a cal lab to get a certificate (often using the wrong test values with tolerances derived from the data sheet) so that they (you) can put the unit to work in their low-end calibration lab or sell it on eBay 'with fresh calibration certificate!'.  I don't see how any of that helps you.  If you have an HP 3458A you can do a better job yourself.  However, the price doesn't surprise me as simply doing the closed-case performance test is pretty quick and straightforward.

[tggzzz]

For anyone interested I received a quote for calibration (no adjustments) £210 with UKAS traceability - excluding shipping costs. I was a little surprised, I had expected more. Not sure what you all think, but possibly too good to be true?

When I tried to get a calibration of a very old Transorb II 10V source, I had extreme difficulty getting one large "UKAS" shop to tell me what I would receive for my money. I was hoping for a statement of equipment used, measured value, uncertainty in the measured value. After several conversations, the staff began to "see what I meant", but left me with zero confidence. I suspect they are really set up to satisfy the "box ticking" culture sufficient for general purpose equipment and usage.

In the end I took it on holiday to the Maker Faire in Hannover, and had its voltage measured by the PTB's hp3458 which they had calibrated the previous day That was sufficient for my purposes

YMMV, of course.

[mendip_discovery]

Find a lab nearby,
https://www.ukas.com/find-an-organisation/browse-by-category/?cat=708

Big labs only care about the customers who will send it lots of stuff regularly and spend loads of money, but they have the good kit and low uncertainties.
Small Labs will take on most stuff and are happy to do the one-off customers. But they don't always have the best kit and have ok uncertainties.

17025 labs will tell you that its for the customer to decide what they want, so I would advise you to ask for their best uncertainties as a basic.

I work in a small lab and I suspect I wouldn't be able to do your kit justice but off the top of my head, I would say CMR (https://www.cmrcalibrate.co.uk/) and Southern Calibration have been good to me in the past. CMR tend to be good on price and tends to turn stuff around quite quickly and if I have had an issue with a cert they have been good and taken the item back and re-done the calibration.

I was hoping for a statement of equipment used, measured value, uncertainty in the measured value.

Why does it matter what kit was used? They could use a very well dialled-in 6.5 digit meter or a very wobbly 8.5 digit meter and still have the same uncertainty. The 17025 schedules for the lab will tell you what they have the ability to do, if they try to put stuff on the cert they can't do then they have to make it very clear it is not covered by 17025 accreditation.  The schedule will also state their best measurement uncertainty.

[tggzzz]

Find a lab nearby,
https://www.ukas.com/find-an-organisation/browse-by-category/?cat=708

Excellent; thanks.

WTF the organisation I approached couldn't have given me the relevant information in those documents will have to remain a subject of somewhat scurrilous speculation.

[TiN]

Since OP has 3458A sending 5100B out for some cheap calibration does not make much sense, unless 3458A itself is broken.

[tom99]

Since OP has 3458A sending 5100B out for some cheap calibration does not make much sense, unless 3458A itself is broken.

No, they're both working. But definitely need a calibration and possibly some adjustments to be done. I think maybe this would be the best option. I don't currently use the full potential of the 3458A though and was reluctant to have them sent away for calibration until my work and things settled a little and had the time again. So it was really just to save some money now and also have a fresh cert for the 3458A's when I actually use them to full potential. Don't suppose anyone with two 3458A's have just sent one off for calibration and then used that one to calibrate the other? If so, was it hassle in your opinion or worthwhile doing?

[alm]

Verifying the performance of one 3458A with another 3458A has two problems:
1. The test uncertainty ratio of the calibrated 3458A to the uncalibrated 3458A (unit under test) is unlikely to be good enough to verify if the unit under test is in spec unless you apply lots of guardbanding, and hence are very likely to find it out of spec. See Fluke Appnote Calibrating the Hewlett-Packard 3458A DMM with the Fluke 5720A Multifunction Calibrator for more information on this. Try going through the math and seeing what you get. The 3458A calibration manual talks about having a 3458A option 2 (high stability reference) calibrated to the 90 day specifications, and that barely allows verification to 1 year limits.

2. You can't just connected two 3458As together and check if they match. You also need a voltage / current / resistance with the right value and frequency (in case of AC). And though the signal doesn't need to be accurate (the monitoring DMM can take care of this), the signal needs to be stable for the duration of the measurement. I've tried comparing two meters (not 3458As) against unstable sources and finding the relation over time between the two meters, but it's a hassle and no standards body would approve. The 5100B could provide most of the signals, except high frequency AC, but I highly doubt the stability and noise will be good enough. Maybe for 6.5 digit, but not for 8.5 digit.

[dl1640]

best to check the 24h stability of 5100b with your 3458a at first, also the linearity can be checked