How To Test RPM Using Multimeter?
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URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=34557
Printed Date: April 26, 2024 at 6:24 PM
Topic: How To Test RPM Using Multimeter?
Posted By: noeljimmy
Subject: How To Test RPM Using Multimeter?
Date Posted: June 25, 2004 at 12:07 PM
can i use a multimeter to test RPM? how i gonna use a multimeter to test RPM? can anybody tell me?
Replies:
Posted By: kgerry
Date Posted: June 25, 2004 at 1:30 PM
you cant
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Kevin Gerry
Certified Electronics Technician
MECP First Class Installer
Owner/Installer
Classic Car Audio
since 1979
Posted By: sandt38
Date Posted: June 25, 2004 at 3:09 PM
You meter must have that capability to perform that function. If it does, you will need a special amp clamp to perform the duty. The Fluke 88A will, but the Fluke 87 will not. Of course, you give up other things too. The 87 is a far quicker, far better meter, but the 88 offers more functionality.
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Posted By: DYohn
Date Posted: June 26, 2004 at 12:27 AM
RPM? Revolutions Per Minute? Uh, I use a Fluke 87 every day and it does not include a tach or strope as far as I know... ------------- Support the12volt.com
Posted By: Javelin3o4
Date Posted: June 26, 2004 at 1:30 AM
if you set the multimeter to AC the tach wire should read anywhere from 1-6 volts, but unless your multimeter has a rpm setting it wont show actual RPM's. Autozone sells a multimeter for 40 bucks that has rpm option. this is the meter i use. https://buy1.snapon.com/catalog/pro_det.asp?P65=&tool=diagnostics&item_ID=16688&group_ID=1367&store=snapon-store&dir=catalog
Posted By: evnldr
Date Posted: June 26, 2004 at 5:43 AM
Javelin3o4
is correct
and reving the motor will make the voltage rise as the rpm dose....
Posted By: kgerry
Date Posted: June 26, 2004 at 11:11 AM
which will give you an AC voltage reading not a true RPM reading...certainly there are devices to monitor this, but i've never owned a DMM that will meter true RPM........and i've owned at least a dozen good handheld meters over the years....
-------------
Kevin Gerry
Certified Electronics Technician
MECP First Class Installer
Owner/Installer
Classic Car Audio
since 1979
Posted By: Javelin3o4
Date Posted: June 26, 2004 at 2:53 PM
Posted By: kgerry
Date Posted: June 26, 2004 at 3:13 PM
i dont doubt it.... Snap On makes great stuff...just more than i would spend for a shop meter....
-------------
Kevin Gerry
Certified Electronics Technician
MECP First Class Installer
Owner/Installer
Classic Car Audio
since 1979
Posted By: sandt38
Date Posted: June 26, 2004 at 8:08 PM
Fluke 88 with a Snap-on Label 
Not a bad meter.
and $425 is a bit much? I don't know, I use mine enough to justify the cost. Dollars to minutes $425 ain't much at all.
Oh yeah, Snap on does not make it's own electrical test equipment ;). Most of it is OTC -------------
Posted By: evnldr
Date Posted: June 26, 2004 at 8:24 PM
Go to pep boys get a cheap tach off the shelf place a lighter cord to it and a probe ??.
use it after you used yer meter on ac to do a test??
just a thought
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Posted By: shaman
Date Posted: June 27, 2004 at 12:09 PM
425, yup that would be retail snapon alright, probbly could get it for less than 300 out the back of the truck and that is STILL way to much, the really nice fluke's are around 150 at sears.
Posted By: sandt38
Date Posted: June 27, 2004 at 8:07 PM
The same Fluke (88A) is a $400 unit, easy. The Fluke 87 is still $350 or so. I paid $395 about 7 years ago for my 87. $425 is not bad for the Fluke 88A, and for $150 you will not touch the functionality and reliability of the 88A.
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Posted By: shaman
Date Posted: June 27, 2004 at 9:15 PM
Well OK if you need the 88, my old 73 Mk.III has served me just fine ($90 bucks on sale). I'm saying that 300-400 bucks is a little extream if the guy just wants to read rpm.
Posted By: shaman
Date Posted: June 27, 2004 at 9:22 PM
OK if you really need the 88, my old 73 Mk.III has served me just fine (90 bucks on sale). Its just that 300-400 seemes a little extream if all the guy wants to do is measure rpms. But if your gonnma spend mony Fluke is definately the way to go. I have worked as a mechanic and snap-on always jacks up the price when they throw their name on stuff. Take a 200 impact produces by BS or CP and put a snap-on cover on it and buy it from the truck, BAM 300 bucks. MAC too. I think this is time to cunsult the God of buying neat stuff...e-bay.
Posted By: shaman
Date Posted: June 27, 2004 at 9:25 PM
Hell my university was selling used DA units like the hydra for that kind of money.
Posted By: Javelin3o4
Date Posted: June 27, 2004 at 10:27 PM
i was just showing which one i use, i use it everyday thats why i have that one, like i said a few posts ago autozone if there is one near you has a DMM that reads RPM for 40 bucks.
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