# how many years can I expect a fluke multimeter to be within its specs



## Viking (May 26, 2012)

How many years can I expect a fluke multimeter to be within its specs ( Or a similar top brand ).

I realize there are no guarantees. But is there any realistic chance it will meet its specs for a lifetime ?


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## Dr Jekell (May 26, 2012)

I may be wrong but I believe that most reputable multimeters can be sent back to the company to be calibrated. 

Edit: Yep they do - Calibration and Repair Services


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## march.brown (May 26, 2012)

Before I retired , we all had Flukes issued and our measurements section used to check them against a calibrated standard every year ... Mostly they were OK but some did have to go back to Fluke to be re-calibrated ... When I retired , I kept my Fluke as that one was only about three years old ... Less than three years after retirement , the Flukes display started to fail as some of the segments died ... At less than six years old , it was thrown out ... I now buy the cheap DMMs and I check them against a very accurate 5.000 Volt (DC) reference ... So far I have only given away one meter though it was still good enough for general domestic use ... It is obvious that the cheap meters are not as well made as the Flukes , but I don't mind that ... Nowadays , I only need real accuracy when measuring my Li-Ion batteries. 

If you need a meter to measure frequency and temperature as well as voltage , then the Fluke is great ... Having been retired now for eighteen years , I simply can't justify the cost of a Fluke ... These two cheapies have lasted so far for about three years and are still very accurate when checked against my reference.
.


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## czAtlantis (May 26, 2012)

I had very old (10+ years) fluke multimeter and after 10 years it was not accurate - difference 0,1V at low voltages (around 5V). Anyways it died few months ago - cracked display.

Fluke multimeters are sooo expensive. I recently bought Minipa ET-997. It is very accurate (tested against other multimeters and Agilent power supply), has many functions and it was around 40USD from DX. When you lost it/crack one of these it is better than 250USD fluke with similar functions...

EDIT:
I usually buy expensive devices istead of cheap low quality ones - for example buying eneloops instead of cheap AA ni-mh cells is justified price increase. But here in Fluke versus others the price difference is just too high and functions/accurancy/quality advantages are not so dominant.


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## pinetree89 (May 26, 2012)

Fluke is the Surefire of the instrumentation world. Made in USA, excellent in every way for the most part. But you're going to pay dearly for the Fluke name. This is ok when you're in business and have to maintain calibration and traceability for everything you test.

However when you're at home checking battery voltages, functionality of a power outlet, or continuity of a switch or circuit, most cheapie multimeters will be more than adequate. 

This from a guy who dropped $300+ on a Fluke 87 a number of years ago, but uses his $4 harbor freight meter 99% of the time.


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## Robin24k (May 26, 2012)

pinetree89 said:


> Fluke is the Surefire of the instrumentation world. Made in USA, excellent in every way for the most part.


Unfortunately, that's not necessarily true anymore...my Fluke 117 was imported. :shrug:


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## HKJ (May 26, 2012)

Generally all DMM's does stay close to calibration, but all DMM manufacturers does recommend a yearly calibration. With calibration you know that the DMM is still correct, but the price of a calibration is rather high, another way is to buy a cheap reference and use it to check a few ranges on the DMM.
I love my Fluke DMM's and nearly always uses them (Except when I uses a Gossen MetraWatt). I have never seen a Fluke fail, but I do also handle them very carefully.
I do have a pile of other DMM's, but mostly I buy these just to see how they work and some of them I would never trust (This depends on what I measures).

For measuring LiIon batteries most cheap DMM's works, but if you really want a realibility, get a (cheap) meter with more digits and a cheap reference.


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## Viking (May 26, 2012)

Usually I buy top brand items. Somehow it gives me a better feel.
But in this particular case maybe I shouldn't , I see your points.


If there's only a little chance a Fluke will keep its specs without calibration , it's hard to justify a buy for my needs.
I don't really need exceptionally good build quality ( It will be a household multimeter ).


For the price of a fluke and regular calibrations , I can probably buy many multimeters.


@ march.brown


Is the 5.000 Volt (DC) reference the one from voltagestandard ?
I haven't seen any others.


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## HotWire (May 26, 2012)

I'm on my third Fluke. The first two had display failures. The cost of having them repaired was almost the same as buying the meter again! I have a very old Radio Shack digital VOM that I use for daily tasks and it plays well with the Fluke. They are almost always very close or the same with low-voltage measurements. Would I pay big bucks for another Fluke. Probably not.

>I know this is an old post, but.... this video brought back the display on one of my old Flukes: http://www.youtube.com/watch?v=WPHsVG8K1so Hope it helps!


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## MattSPL (May 26, 2012)

I have a Fluke DMM that i bought in 2003. I'm an electrician, so it has seen plenty of use and abuse along the way. I only just replaced the battery for the 2nd time since new.

It's doing a good job of measuring different cr123 LifeP04's at the moment, so seems pretty accurate still.


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## 45/70 (May 26, 2012)

I have a Fluke 27/FM that I bought from a friend a few years ago. It was manufactured in 1996 and the U.S. Army calibration expired some time ago (2011?). I had it checked against a Fluke 8808A a few months ago (which is sent out yearly for calibration), and it is "in spec".

The unit is a 3 1/2 digit 3200 count DMM, and DC Volts are spec'd at +/- 0.1% + 1 digit. The guy who checked it put it another way when I was talking about checking Li-Ion cell voltages. He said that better than 2 out of three times this particular DMM would round to the correct hundredth of a Volt, at 4.20 Volts. +/- 0.01 Volt is good enough for me. I have two 4 1/2 digit (80,000 and 20,000 count) bench meters, if it's really all that important, which it never is.

As for durability of the Fluke meters, I like the 27, 27/FM, 28 versions. These are pretty much functionally, the same as the Fluke 85 and 87 (although the "27" was not "true RMS" on AC), but are larger, sealed/waterproof, and in addition, are drop tested from 3 meters, rather than the measly 1 meter that the 85/87 were tested, LOL! If I ever go for a new handheld DMM, I'll likely go for a 28II. Yes, overkill, but better accuracy, precision, and a few extra features that I'll probably never use.

Dave


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## jasonck08 (May 27, 2012)

Dr Jekell said:


> I may be wrong but I believe that most reputable multimeters can be sent back to the company to be calibrated.
> 
> Edit: Yep they do - Calibration and Repair Services



You can, but you will pay dearly for their services. I think it was either $75 or $100 I was quoted to get my Fluke 197 calibrated. The meter cost me less than $200, so no way will I shell out that kind of money just to have it calibrated. It's about 2 years old, and still is in perfect calibration when compared to my more costly Agilent meter. I'm also still operating on the factory 9v cell. Amazing battery life!


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## Russel (May 27, 2012)

pinetree89 said:


> [...]However when you're at home checking battery voltages, functionality of a power outlet, or continuity of a switch or circuit, most cheapie multimeters will be more than adequate.[...]



Keep in mind that using a cheap multimeter on high voltage circuits is a bad idea. Using a cheap multimeter for checking battery voltages, switch continuity, or other low energy testing is fine. But, I would only use a high quality multimeter with high energy fuses, high voltage input protection, and good quality test leads to measure house power outlets. Safety can be an expensive consideration, but very important.


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## BringerOfLight (May 27, 2012)

Viking said:


> Is the 5.000 Volt (DC) reference the one from voltagestandard ?
> I haven't seen any others.


You can easily build one yourself. E.g. with something like the LM4040 (0.1% accuracy), you only need 2 resistors in addition to the LM itself.

https://www.national.com/ds/LM/LM4040.pdf


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## 45/70 (May 27, 2012)

The biggest problem with obtaining a voltage reference is that they are only good once you receive them, for 6 months to a year. Just like DMMs, they have to be checked/calibrated occasionally. I would think this applies to making one yourself. You would still have to compare it to something, and calibrate it, before it's good to go, and then check it every once in a while.

I've often thought about getting a voltage reference. It is awkward taking my meters every so often and having them checked. In fact, the last time I only took the previously mentioned Fluke, and the smaller of my 4 1/2 digit DMMs.

For most people, I would think the money spent on a voltage reference, would be better spent towards a higher quality meter. Then check it against a meter that is calibrated annually once in a while, if possible. For most of us, it wouldn't need to be checked all that often.

Dave


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## HKJ (May 27, 2012)

45/70 said:


> For most people, I would think the money spent on a voltage reference, would be better spent towards a higher quality meter. Then check it against a meter that is calibrated annually once in a while, if possible. For most of us, it wouldn't need to be checked all that often.




If you have access to a calibrated DMM, that is a very good solution, but if you do not have a reference is not that expensive.
If you buy a reference you will also know what is most precise: The DMM or the reference. The reference is much more precise than any cheap DMM.
With two DMM's you do not really know which one is correct.


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## Viking (May 27, 2012)

45/70 said:


> The biggest problem with obtaining a voltage reference is that they are only good once you receive them, for 6 months to a year. Just like DMMs, they have to be checked/calibrated occasionally.



The calibration fee for the reference is only 5 - 7,5 $ , depending on which model you have. plus additional 3 dollars for shipping within the US , overseas a little more off course.


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## 45/70 (May 28, 2012)

HKJ said:


> If you buy a reference you will also know what is most precise: The DMM or the reference. The reference is much more precise than any cheap DMM.



Ya, I follow you here. Good point, but still eventually......



> With two DMM's you do not really know which one is correct.



This was sorta my point. Once the reference is a year or two old (without sending it back and and having it checked/calibrated), you're in the same situation. The reference is really no different than having an additional DMM, at least concerning better quality DMMs anyway.



Viking said:


> The calibration fee for the reference is only 5 - 7,5 $ , depending on which model you have. plus additional 3 dollars for shipping within the US , overseas a little more off course.



Well, this is something I hadn't considered, I guess. That's not too bad at all. I just may look around and pick one up, if it seems viable and has a good "plan".

Dave


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## Vinniec5 (May 28, 2012)

march.brown said:


> Before I retired , we all had Flukes issued and our measurements section used to check them against a calibrated standard every year ... Mostly they were OK but some did have to go back to Fluke to be re-calibrated ... When I retired , I kept my Fluke as that one was only about three years old ... Less than three years after retirement , the Flukes display started to fail as some of the segments died ... At less than six years old , it was thrown out ... I now buy the cheap DMMs and I check them against a very accurate 5.000 Volt (DC) reference ... So far I have only given away one meter though it was still good enough for general domestic use ... It is obvious that the cheap meters are not as well made as the Flukes , but I don't mind that ... Nowadays , I only need real accuracy when measuring my Li-Ion batteries.
> 
> If you need a meter to measure frequency and temperature as well as voltage , then the Fluke is great ... Having been retired now for eighteen years , I simply can't justify the cost of a Fluke ... These two cheapies have lasted so far for about three years and are still very accurate when checked against my reference.
> .



If it was a Fluke 87, there was/still is a repair avail for led fade. it can still be found for $30 or so on EBay. common on the older 87s. the 87V is still a top notch meter


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## majorm (May 29, 2012)

I have been lurking on this site for a while now but I may can shed some light on this topic. 

I own a calibration lab and calibrate multimeters all the time. So they do not need to go back to Fluke or the mfg per say. As far as the typical calibration period the easiest way to put it is it depends. Most of the meters I deal with are from plants and are used daily and not cared for the best. The normal calibration period is once a year for most meters. Sometimes the meters will fall within the specs and sometimes they wont. From my normal customers I would say for the most part atleast one area in the performance test has to be tweaked back into specs per year. The thing to consider is what is YOUR tolerance for the accuracy of the meter. You may not need the accuracy the meter provides so you might could extend or shorten the calibration period based on that. 

One thing to consider if your thinking about just buying one cheap meter a year to replace a more expensive option is that how do you know the cheap meter works from the start? It may not be off but yearly or even every two years between calibrations gives you the piece of mind it is right. I havent dug into the cheap meters like the harbor freight ones but with many of the better made ones there are adjustments to bring them back into specs. So if it is out it usually isnt a big deal to bring them back in. 


If you have any questions on the calibrations feel free to ask. 

Major


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## 45/70 (May 29, 2012)

Hi Major, and welcome to CPF!:thumbsup:



majorm said:


> ......Sometimes the meters will fall within the specs and sometimes they wont. From my normal customers I would say for the most part atleast one area in the performance test has to be tweaked back into specs per year......
> 
> ......One thing to consider if your thinking about just buying one cheap meter a year to replace a more expensive option is that how do you know the cheap meter works from the start? It may not be off but yearly or even every two years between calibrations gives you the piece of mind it is right.



Would you say that the likelihood that a meter needs recalibration is the same for less expensive meters vs. higher quality ones, or is the need simply proportionate to the accuracy of the meters? In other words, obviously a meter that is +/- 0.025% +1 is more likely to be out of spec than a meter that is +/- 1% +3, or is it?

I hope that makes sense. I'm in a bit of a "crunch" today.

Dave


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## desirider (May 29, 2012)

Hi Major,

Welcome to CPF! It is good to have a calibration expert on-board  I am newbie here myself.

Calibration is always fascinating. It is mind boggling how accurate the calibration equipment really are. Even an off-the-shelf Fluke 8846a is accurate to 25-40 ppm! I can only imagine the calibration standards being an order-or-magnitude more accurate.

I have a Fluke 8600A that was made in the 1970s and was used in a lab until the 2002/2003. It was last calibrated in 2002 and I just compared it to my lot-newer Fluke 175 and it is spot on. Can you imagine a 4.5 digit (20,000 count) DMM with a basic DC accuracy of 0.02% designed and built in the 1970s? Heck, even the built-in rechargeable battery works, although there is a good chance that the battery must have been replaced. Still, it is 10 years old!

Cheers,
Desirider.


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## march.brown (May 29, 2012)

Viking said:


> @ march.brown ... Is the 5.000 Volt (DC) reference the one from voltagestandard ? ... I haven't seen any others.



I bought mine on 17th February 2010 on Ebay ... It was advertised as "Precision Voltage Reference Source 5.000V 0.2%" ... It was certified as 5.0002V at 72F ... It cost $20-15 including postage from the US to the UK ... The Ebay seller was rdana who is actually DanaCo.net ... 

I am not sure whether they are still selling these items ... It is a small PCB (30mm X 75mm) with a few components on it plus an ON/OFF switch and a mount for a small 9V (MN1604) battery ... Sorry I can't give you any more information , but it might be worth contacting DanaCo.net.
.


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## majorm (May 29, 2012)

Thanks for the welcomes.

45/70: What I was getting at with the HF example was they built it to a more lenient spec. So depending on how wide they made it the meter could stay within that range for a long time. However on that same note with cheaper components did the meter just barely make specs when it was made? Thats where the calibration comes in. It gives you a baseline to go from. Most of the time unless there was damage to the unit a meter will drift out of tolerance. On the voltage ranges many meters will give high readings if they have low battery voltage. So thats something else to consider. Going to your accuracy tolerances that is a gray area since the meter could have fallen right at nominal when it was made or it could fall at the edges. I doubt they adjust the HF meters back into a certain spec unless they just use a couple quick test points. The Fluke however would be more likely to fall closer to nominal due to better components. The thing to think about though is the resolution was the same with your example is that even if the better meter was out even 2x to be generous the tolerance its still potentially more accurate than the cheap one brand new. I hope that made more sense. 

NoI'mIm tempted to go buy a HF meter just out of curiosity. They would have to be less than a mile from the office. 

desirider: Yep it is an interesting field and hard to believe how close we can create measure and create a certain value. We have a older HP 3458A that we used to use but have a Fluke 8508A too and while the 3458 is just as good in many ways the 8508 is just easier to use. Many of the older pieces of equipment were just built well and still work great. They just usually aren't as user friendly.


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## Viking (May 30, 2012)

march.brown said:


> I bought mine on 17th February 2010 on Ebay ... It was advertised as "Precision Voltage Reference Source 5.000V 0.2%" ... It was certified as 5.0002V at 72F ... It cost $20-15 including postage from the US to the UK ... The Ebay seller was rdana who is actually DanaCo.net ...
> 
> I am not sure whether they are still selling these items ... It is a small PCB (30mm X 75mm) with a few components on it plus an ON/OFF switch and a mount for a small 9V (MN1604) battery ... Sorry I can't give you any more information , but it might be worth contacting DanaCo.net.
> .




Thanks I didn't found it , but I have found another 5.0000 V DC reference with an accuracy of 0.0025%




@ majorm

Thanks for your post , it was very informative.

And BTW welcome to cpf


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## somename (May 30, 2012)

I have a cheap meter that I've been using for the past 8 years as well as a cheap bench top multimeter and a Fluke 179 meter. Noticed the other day was gonna use the cheap one and the voltage reading with it on a 6V lead acid battery was WAY off. Figured its been many years since the battery was changed. New 9V battery and presto, reads right back with the other 2 meters again.

Seems the difference is the Fluke reads consistent all the way till the batteries are completely dead where as the cheap ~$20 meter was reading off without even the low battery light on.


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## BringerOfLight (May 30, 2012)

45/70 said:


> The biggest problem with obtaining a voltage reference is that they are only good once you receive them, for 6 months to a year. Just like DMMs, they have to be checked/calibrated occasionally. I would think this applies to making one yourself.


Yes and no. The primary aging factor with one of those single-chip voltage references will be operating hours. If you only use the reference once a year to calibrate your multimeter, that 0.1% LM4040 will be more than sufficient for your typical 0.5% accurate multimeter for a very, very long time.

BTW, I mentioned the LM4040, not because it's particularly accurate/great, but because it's extremely cheap, easily available, very easy to use and probably accurate enough for 99% of the people...


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## 45/70 (May 30, 2012)

majorm said:


> ......I hope that made more sense.



Thanks for the explanation, major. I can follow that.



BringerOfLight said:


> Yes and no. The primary aging factor with one of those single-chip voltage references will be operating hours. If you only use the reference once a year to calibrate your multimeter, that 0.1% LM4040 will be more than sufficient for your typical 0.5% accurate multimeter for a very, very long time.



Understood. As I mentioned in another thread recently, if your serious about measuring Li-Ion cell voltages, my personal preference would be a meter along the lines of 0.1% (or better) DC Volt accuracy. It's not that you couldn't get away with 0.5, or even a 1% meter, but for example the maximum CV voltage (and thus the maximum fully charged voltage) for charging LiCo Li-Ion cells is 4.20 Volts +/- 1%, or ~4.15-4.25 Volts. So with a 1% accuracy meter it's possible that your meter is out of bounds by approximately 0.05 volt either way, if it's at the "edge". On the low end 4.10 Volts is not going to cause any problems. On the high end 4.30 Volts is not likely to either, but if your serious about it......

So anyway, it does make more sense to me now for one to obtain a voltage reference. The relatively low cost of sending one back for checking/recalibrating, as I said, is something I hadn't considered, and does make it a practical solution.

I'm not as OCD about this kinda stuff as I used to be, but as you can probably tell, there's still a hint present.

Dave


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## Russel (Jun 1, 2012)

I just received received a DMMCheck from voltagestandard.com and tested a couple of my better meters. My old Fluke 863 was pretty much dead on. My newer Agilent U1251A was close, but not quite dead on. I don't remember exactly how old the 863 is, but it has never been calibrated in all the years that I have had it. When I get a chance I will post the actual numbers.


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## Viking (Jun 1, 2012)

Russel said:


> My newer Agilent U1251A was close, but not quite dead on.



Do you know , if it was still within its specs ?


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## Russel (Jun 1, 2012)

I checked my old Fluke 83 III here at
work, the voltage is good, but the resistance measures pretty far
off. I'll post the numbers for all three meters when I get home
tonight. The DMMCheck standard is a pretty good alternative (I have
no affiliation with voltagestandard.com other than being a customer)
to more expensive meter calibration. I don't really need super
accuracy, but it's good to know how accurate my meters are.


```
Voltage standard           Fluke 83 III
5.0000V                       5.00 (40V scale)

0.9997mA                    999. micro amps (Rel used, 4000 microamp scale)

999.5 Ohms                .999K (Rel used, 4K scale)

10.005K Ohms              9.91K (40K scale)

100.07K Ohms              89.8K Ohms (400K scale)

Battery 9.52V                Battery 7.87V
                           (no low battery warning)
```


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