Digital multi meter not accurate

Thread Starter

sangpo

Joined Aug 17, 2013
91
I have recently bought multi meter on line. I measured the new 9 DCV with this multimeter but the reading is 10.76 DCV which is not correct.
what could be the reason?
 

dl324

Joined Mar 30, 2015
16,911
I have recently bought multi meter on line. I measured the new 9 DCV with this multimeter but the reading is 10.76 DCV which is not correct.
what could be the reason?
I assume you're measuring a battery. A fresh 9V battery, it will read higher than 9V.
 

Thread Starter

sangpo

Joined Aug 17, 2013
91
A fresh 9V battery will read higher than 9V.
10.76V seems rather high.
yes sir, it is. It measure the almost accurate with other multimeter.
So that means this multi-meter will not serve any suppose. ?
Better throw if there is no option for calibration
Thank you
 

Reloadron

Joined Jan 15, 2015
7,515
A man with two watches will never know the correct time and a man with two meters will never know the correct voltage. What you don't have is a known accurate meter. If you know one meter to be correct and compare it to another meter you at least have a known to compare to an unknown. If you know the new meter is giving incorrect readings with significant error you can return it to the manufacturer or return it to the retail outlet you got it from. Most new handheld DMMs do not easily allow calibration adjustment or if it does then get a good known and calibrate your inaccurate meter against it. You also need a good stable source for your parameters to be measured.

Ron
 

MrChips

Joined Oct 2, 2009
30,795
For example, you can use a 3-terminal linear regulator such as 7805 as a starting point.

I have a Weston standard mercury cell that was calibrated in 1947 and it still reads very close to the 1.0190V printed on the label on the back of the cell.
 

Reloadron

Joined Jan 15, 2015
7,515
For example, you can use a 3-terminal linear regulator such as 7805 as a starting point.

I have a Weston standard mercury cell that was calibrated in 1947 and it still reads very close to the 1.0190V printed on the label on the back of the cell.
Fond memories. :)

Ron
 

Audioguru

Joined Dec 20, 2007
11,248
Name-brand multimeters are usually accurate but are fairly expensive. No-name-brand multimeters made "over there" are not accurate but they are cheeeep. Was your multimeter cheeeep?
My expensive Fluke multimeter is about 28 years old and still works perfectly.
 

spinnaker

Joined Oct 29, 2009
7,830
A man with two watches will never know the correct time and a man with two meters will never know the correct voltage. What you don't have is a known accurate meter. If you know one meter to be correct and compare it to another meter you at least have a known to compare to an unknown. If you know the new meter is giving incorrect readings with significant error you can return it to the manufacturer or return it to the retail outlet you got it from. Most new handheld DMMs do not easily allow calibration adjustment or if it does then get a good known and calibrate your inaccurate meter against it. You also need a good stable source for your parameters to be measured.

Ron

But a man with a watch that is no longer running will know it is accurate twice a day. ;)
 
Can you confirm the model of dmm that you are having the voltage/measurement with?
10+v is too high, I would think the meter has not been correctly calibrated.
 
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