Fluke DMMs

[signcrafter]

I think my luck keeps going down! I had a thread a while ago about getting a blue point meter used off ebay and it not matching what my fluke meters say. I have 2 flukes, a 16 and a 77 which are almost dead on with each other. When measuring a battery they are either right on a hundredth off which to me is good enough. The blue point meter is .14 volts off then those two flukes. Which isn't a huge deal for most tests but it's still not very close in my opinion. So I have been on a look out for a fluke 87 or 88. I found a used 87 and decided to pick it up. Hooked all four meters to a car battery I had sitting around and the 16 and 77 read 12.44, the BP read 12.59, and the 87 read 12.67. So the 87 which probably should be the most accurate out of the 4 meters is .23 volts off from my other two flukes.

So what would you say from these measurements? Am I safe to assume that the BP and fluke 87 are off since the other two flukes read the same?

 

[litljay]

Do all 3 have new/known good batteries in them? Sometimes if the battery is suffering, it will cause the meter to give you a false reading.

 

[Alan Douglas]

The chance of two different meters reading exactly the same and both being wrong is extremely low. There must have been a reason the previous owner sold the 87.

I use my Fluke 79 as a reference for checking other meters. Flukes are pretty reliable but then I know the history of mine since I bought it new.

 

[Givl Reggin]

Hooked all four meters to a car battery I had sitting around and the 16 and 77 read 12.44, the BP read 12.59, and the 87 read 12.67.

Pick the one meter you like and send it off to the Fluke service center... they will repair/replace/recalibrate for a flat fee of $75. I did this years ago for a meter that had a cracked lcd display and it came back with some kind of ISO certification sheet that detailed the accuracy/ranges.

 

[rusty65]

Your problem is that fluke meters only give fluke readings.

 

[Alan Douglas]

There was a competitor that used to advertise "It's no fluke."

 

[jerryd68]

Around here the local electrical distributor that carries Fluke meter hold's an annual calibration day, they have a rep from Fluke come out and do the calibrations.

 

[Givl Reggin]

"It's no fluke."

Simpson? I have a Simpson bench top meter that's about as good as it gets.

 

[signcrafter]

Pick the one meter you like and send it off to the Fluke service center... they will repair/replace/recalibrate for a flat fee of $75. I did this years ago for a meter that had a cracked lcd display and it came back with some kind of ISO certification sheet that detailed the accuracy/ranges.

Really? That sounds like the way to go, send in the 87 and have it calibrated. I'll have to look into that. Thanks

 

[box]

Pick the one meter you like and send it off to the Fluke service center... they will repair/replace/recalibrate for a flat fee of $75. .

its a lot more then $75 for a flat rate repair these days...i forget the exact # but it was pushing $200 for a Fluke 88 recently

 

[zkling]

Where are you located?

Try using the same leads in each meter. Then see if they still give different readings. Also try both auto and manual ranging modes on each meter, see if the readings are different.

You really need to find a bench standard. Do you know any local folks that are into hamb radio or other hi techish electronics? They usually have really high end scopes and the like.

Of the meters you have I would get the 87 calibrated. They are easy to calibrate, just need a known reference to calibrate to.

 

[signcrafter]

its a lot more then $75 for a flat rate repair these days...i forget the exact # but it was pushing $200 for a Fluke 88 recently

Well that burst my bubble. I don't think 200 would be worth it.

So if you guys were just a home mechanic which meters would you use or keep? I'm thinking I'm going to sell at least two of them. Or try to sell all of them and see if I can get enough money for a brand new meter. Is the fluke 87 accurate enough for most testing being off by .23 volts? That is assuming the other two flukes that read the same are right.

 

[redwrench60]

That Fluke 87 should have higher DC accuracy than any of your other meters. Unless it's taken a hard shot to the nuts I'd trust it. I have three 80 series flukes and worked with many more including an 87 that belongs to the shop. Talk about a battered *************. It still works perfectly.

 

[zkling]

Where are you located? Did you try any of my above suggestions?

Have you tried checking other voltages? How about AC? Is the 87 consistently off?

 

[signcrafter]

Where are you located? Did you try any of my above suggestions?

Have you tried checking other voltages? How about AC? Is the 87 consistently off?

No I didn't and don't have the meters with me tonight. Will do some more checking tomorrow. I did switch leads between the fluke 77 and 87 and the readings stayed the same so I don't think it is the leads. I will try and measure an AC outlet tomorrow and see what I get.

This may be a silly question but is there any settings I should be making sure I'm on? Like auto ranging or any other special settings the 87 may have that may affect the readings? Or just turning them on to DC voltage and hook up leads they should all be the same?

 

[zkling]

No I didn't and don't have the meters with me tonight. Will do some more checking tomorrow. I did switch leads between the fluke 77 and 87 and the readings stayed the same so I don't think it is the leads. I will try and measure an AC outlet tomorrow and see what I get.

This may be a silly question but is there any settings I should be making sure I'm on? Like auto ranging or any other special settings the 87 may have that may affect the readings? Or just turning them on to DC voltage and hook up leads they should all be the same?

Should be ready to go. I am not familiar with the other meters besides the 87. It's been a while since I used my 87 as I usually reach for the 27, but IIRC it should auto default to auto ranging when set to DCV. From that you can hit the "Auto" button at the top and go from there. They should all read the same wether set on auto or manual, but if they don't it would signal a problem.

Where are you located? I feel like you and I have discussed multimeters a few times.

 

[oldtools]

You can buy a brand new HF meter and use it to test your other meters.

http://www.harborfreight.com/7-function-digital-multimeter-69096.html

 

[zkling]

You can buy a brand new HF meter and use it to test your other meters.

http://www.harborfreight.com/7-function-digital-multimeter-69096.html

I would at least wait till it goes on sale for $0.99

 

[signcrafter]

You can buy a brand new HF meter and use it to test your other meters.

http://www.harborfreight.com/7-function-digital-multimeter-69096.html

I think that's the same one they give away for free and I have a handful of them. Keep one in the car and give them to the kids to play with or to friends that don't have one. I did compare a HF meter one time to my fluke 77 and they were right on if that says anything about them. I was a little surprised it was that close since it was free.

 

[oldtools]

I think that's the same one they give away for free and I have a handful of them. Keep one in the car and give them to the kids to play with or to friends that don't have one. I did compare a HF meter one time to my fluke 77 and they were right on if that says anything about them. I was a little surprised it was that close since it was free.

I was surprise too.

http://www.garagejournal.com/forum/showthread.php?t=153286&highlight=Fluke

 

[oldtools]

Send me all your meters and I will test them against several of my free HF meters. If somehow they are lost during shipment back to you, it is not my fault.

 

[magova1104]

I use my Fluke 88 everyday in the automotive field. I tried some other brands before like Beckman, Tektronix, Wavetek,BK and even Ferret Instruments (95 Model) and I have to say that the best Automotive Meter I've used is the Fluke 88.

As someone said here: "life is too short to use cheap tools"

 

[nissan_crawler]

I think that's the same one they give away for free and I have a handful of them. Keep one in the car and give them to the kids to play with or to friends that don't have one. I did compare a HF meter one time to my fluke 77 and they were right on if that says anything about them. I was a little surprised it was that close since it was free.

Yep, mine is almost dead on with my fluke 88 with dc voltage and ohms (all I checked), go figure.

 

[APEowner]

Any precision instrument needs to have the calibration checked (and probably adjusted) on a regular basis. I don't know what your location is but you may be able to get that done locally.

 

[signcrafter]

I tried some more testing today after putting new batteries in them all. On AC the 87 was 1 volt higher then the 16 or 77. Tested a 9V battery and the 87 was a few hundredths of volts higher then the other two. Looks like the 87 is a little higher then the other two meters on everything I tested.

 

[richfinn]

If your using it to fix cars I would live with it, does it go to 0.00v when set to DC volts if you touch the probes together?

What ohms reading do you get when you touch the probes together?

Don't forget it's true RMS on AC (so you may get a small difference anyway compared to your other meters).

 

[signcrafter]

So the real question now is which meter or meters should I keep? I don't really want to put much more money into my search for a meter. I probably have around 225 bucks total into all of these spread out over the last 10 years or so. Do I keep the 87 which is a true RMS. Or keep the blue point which is similar to a fluke 88 with the RPM clamp. Or keep either the 77 or the 16 which I'm guessing are the two that are calibrated since they read the same.

Is .23 volts off ever going to matter in diagnosing car issues?

I wish I had the money to just go out and buy a new fluke or other quality meter and just be done with it but not an option right now. I could sell all 4 of these and hopefully get a couple hundred bucks and buy something new? Just not sure what my best option is?

 

[redwrench60]

Since the 87's DC and true RMS AC accuracy is higher do you think the other meters are just averaging the reading different? Do you have access to anyone else's 87 to compare to yours?

 

[richfinn]

So the real question now is which meter or meters should I keep? I don't really want to put much more money into my search for a meter. I probably have around 225 bucks total into all of these spread out over the last 10 years or so. Do I keep the 87 which is a true RMS. Or keep the blue point which is similar to a fluke 88 with the RPM clamp. Or keep either the 77 or the 16 which I'm guessing are the two that are calibrated since they read the same.

Is .23 volts off ever going to matter in diagnosing car issues?

I wish I had the money to just go out and buy a new fluke or other quality meter and just be done with it but not an option right now. I could sell all 4 of these and hopefully get a couple hundred bucks and buy something new? Just not sure what my best option is?

If you disconnect a coolant temp sensor on almost any car and measure the ref voltage you should have exactly 5v with the ignition switched on if you need a quick calibration check.

Try the other tests I mentioned particularly the 0.00v DC check

If it passes these 3 tests its fine for diagnosing vehicles.

 

[signcrafter]

Since the 87's DC and true RMS AC accuracy is higher do you think the other meters are just averaging the reading different? Do you have access to anyone else's 87 to compare to yours?

Honestly I don't know. My usage of a meter is pretty basic auto and home use. I've only had basic meters also so don't really know much about the different features either. I guess I was just assuming that the two flukes, the 16 and 77 that were reading the same were reading correct. But that was just an assumption. Maybe the 87 is the correct one and the two lower flukes are off. My blue point which also looks like a "higher end" meter is in between the two flukes and the 87. So maybe the 87 is right, the BP is close and the other two meters are the ones that are off. I don't really know.

If you disconnect a coolant temp sensor on almost any car and measure the ref voltage you should have exactly 5v if you need a quick calibration check.

I will have to look into this.

Try the other tests I mentioned particularly the 0.00v DC check

If it passes these 3 tests its fine for diagnosing vehicles.

 

[oldtools]

You stated that the Fluke 77 is right on with the HF which mean the Fluke 16 is also right on with the HF. With three meters right on, then most likely the 87 and Blue Point are off.

 

[redwrench60]

My suspicion is that none of the meters are off. They just have different accuracy levels with the way they average their readings. This relates to their design intent. Even the other flukes won't have the same reading as the 87. Maybe the blue point reads the same because it has the same accuracy specs.

None of my other meters read exactly the same as my 87's. but all my 87's read the same.

 

[metaldad]

I have many Flukes, but not a 80 series.
just some of the collection:

 

[signcrafter]

Do they all read the same voltage if you hook them up to a car battery?

 

[metaldad]

Do they all read the same voltage if you hook them up to a car battery?

if that's at me......... i dunno.
i don't work on cars for a living
good qwestion.
something to check on the weekend

 

[signcrafter]

if that's at me......... i dunno.
i don't work on cars for a living
good qwestion.
something to check on the weekend

Yes that was for you. What about AC voltages, do all yours read the same there? I'm just trying to figure out if one or more of mine are actually off or if they are getting different readings because of the different meters or what the deal is with mine. Frustrating.

 

[zkling]

I have many Flukes, but not a 80 series.
just some of the collection:

Heck yea, another 27 fan . Honestly it is my favorite and go to multimeter. Super accurate and indestructible. Mine (x2) are ex military units that I bought years ago. Checked a few times and they are both dead on.

YI'm just trying to figure out if one or more of mine are actually off or if they are getting different readings because of the different meters or what the deal is with mine. Frustrating.

Just to reiterate this, THE ONLY way to properly calibrate a meter is to check it against a KNOWN, calibrated reference that is more accurate than the meter you are calibrating. No placing the leads together B.S. Otherwise you are just taking stabs in the dark. How much time and money have you wasted on trying to get a "good" multimeter? And now you have 4 meters, none of which you are able to trust.

My suggestion, pay or somehow get the 87 calibrated, if it checks out then sell your other meters. That way you will have one good working meter that will be able to do probably everything you need it to be able to do.

Yes that was for you. What about AC voltages, do all yours read the same there?

Yes, all of my meters read the same. I have one that I had fully calibrated and use that to calibrate the others. Nothing more useless than measuring equipment that doesn't measure properly.

Something kinda funny, I just tried this tonight. All meters (Cheap cman/extch, fluke 87, fluke 27, fluke 27), my battery measures 12.66v. A few years old, seems to start properly. Just a coincidence that your 87 measures 12.67

 

[zkling]

Since the 87's DC and true RMS AC accuracy is higher do you think the other meters are just averaging the reading different? Do you have access to anyone else's 87 to compare to yours?

That wouldn't cause them to be off that much, I don't think. Since I can't sleep, I calculated the max and min respective of their manufactures stated accuracy includin LSD error.

Meter Measured accuracy (VDC) High Low
fluke 16 12.44 0.9% +1 0.009 12.55 12.33 12.56 12.32
fluke 77 12.44 0.3% +1 0.003 12.48 12.40 12.49 12.39
fluke 87 12.67 0.05% +1 0.0005 12.68 12.66 12.69 12.65
BP 12.59 0.5%+1 0.005 12.65 12.53 12.66 12.52

 

[oldtools]

Here are some of my meters comparison. 2 Fluke, 4 HF, and 1 CM. Lowest (9.96 V) to highest (10.08 V) is about 1.2% difference. The 3 free HF meters did pretty well. They are all measuring the same 9V battery. All the meters are bought brand news and have very very little use except for the large HF meter in the background. That one has quite a bit of usage.

 

[redwrench60]

Here's something else were not factoring in here: all these different meters's test leads and their varying levels of wear, resistance and build quality.

Here's a thought. Pick a set of leads and try them in every meter on a fixed DC voltage source. Say a 9 volt battery that's new or from a device that's been at rest for a while.

I'm trying to see if the different readings are the result of the test leads and not the meters at all.