Multimeter reading

[elecLear78]

Suppose my input voltage is fluctuating continuously does the multimeter reading also fluctuates. Does the multimeter give instantaneous or average value for a digital signal fluctuating continuously?

 

[Inquisitive]

Do you have it on the correct setting? If you read it on the wrong setting it will bounce. Can you provide more details.

 

[MaxHeadRoom78]

Often the update on the average meter is relatively slow, if wanting to keep closer track of the variation, many have a bar graph running below the digits that give you an idea.
If the digit update time was instantaneous the digits would blur together.
Max.

 

[audioguru]

A cheap (not RMS measuring) multimeter shows the average voltage but slow variations are also shown.
Some cheap multimeters mix DC with AC which is confusing and results in the wrong measurement.

 

[KeepItSimpleStupid]

Not quite "Average", because the average of a sine wave is mathematically zero. MOST meters are "Average responding", RMS reading. The "Average" is computed from the full wave rectified signal. RMS reading means this is multiplied by a fudge factor, such that the voltage of a sine wave reads the same as an equivalent DC voltage or the TRMS (True Root Mean Squared).

Which is exactly like it sounds the square root of the average of the value squared.

 

[audioguru]

If the AC or DC voltage is fluctuating then a cheap multimeter shows the average voltage.

 

[KeepItSimpleStupid]

Well, if it did the average of a rectified, sine wave, the voltage read would be 0.63*120 or 75.6 Volts.

https://www.wolframalpha.com/input/?i==average(sin(x))+from+0+to+PI

 

[chemelec]

Suppose my input voltage is fluctuating continuously does the multimeter reading also fluctuates. Does the multimeter give instantaneous or average value for a digital signal fluctuating continuously?

If your trying to measure an Audio Output, You will not get correct readings.
It Varies too much in Voltage.

 

[audioguru]

When I talk about "average AC measurements" I mean that if an AC signal fluctuates continuously from 5V to 15V then its average is shown to be 10V. The meter does not show the 15 peak instantaneous voltage.

Cheap multimeters are designed to measure low frequency AC mains like only 50Hz or 60Hz. They measure higher audio frequencies inaccurately with too much attenuation.

 

[JimB]

Suppose my input voltage is fluctuating continuously does the multimeter reading also fluctuates.

Yes.
If the meter did not respond to a change in the parameter which it was measuring, it would not be a good meter. Would it?

Does the multimeter give instantaneous or average value for a digital signal fluctuating continuously?

Who knows?
Read the specification for the meter.

But first, define what you mean by a "digital signal fluctuating continuously".

JimB

 

[Reloadron]

Suppose my input voltage is fluctuating continuously does the multimeter reading also fluctuates. Does the multimeter give instantaneous or average value for a digital signal fluctuating continuously?

Beats me? What meter and what exactly does "fluctuating continuously" mean? The AC mains power in my house changes 60 times per second but my meter reads stable. Your question needs much more information to get a good answer.

Ron