Hi.

How to view the RMS value of waveform for power dissipation in Waveform Viewer.

LTspice v.17.0.36.0

I am able to view RMS value for Voltage and Current

Waveform separately by simply

Ctrl+LeftMouseClick on the

label of the waveform.

But when Press Ctrl+LeftMouseClick on the

label

of the Waveform of Power

dissipation (Obtained using Alt+Left Click over component) I can View only

Average and Integral Values.

Thank You.

 

That gives the average of the instantaneous real power, which is RMS power.

 

The average of Instantaneous of real power in case of a sinewave voltage and Capacitor or Inductor is 0 , which is not true for RMS value

 

The average of Instantaneous of real power in case of a sinewave voltage and Capacitor or Inductor is 0 , which is not true for RMS value

RMS power is the power dissipated.
An ideal capacitor or inductor dissipates no real power, so the power is all reactive and the real power value is zero.
Why do you think it's not?

 

In Ltspice
In circuit consisting of AC Sinewave Voltage 50Hz an pure Inductor (with negligible series resistance)
When I Press Alt+LeftMouseClickKey on Inductor to view its power dissipation

and then Ctrl+LeftMouseClick on the label of the Power in Waveform Viewer it shows values for
-Average
-Integral
That are negligible or almost zero.
That is not the case with RMS Power.
How to plot and see RMS Power?

 

That are negligible or almost zero.
That is not the case with RMS Power.

Not true.
What part of; A pure inductor dissipates zero real (RMS) power did you not understand?

 

How to plot and see RMS Value?
Although it is zero in case of pure Inductor.

Not
Average
Integral

I want to see
Average
RMS
The same as with the waveforms of Voltage and Current.

 

In case of circuit with
50Hz AC Sinewave Voltage Source
and
Pure Inductor

When I Press alt+mouseleftclick on inductor

I have v*i Waveform in Waveform viewer.
---------------
When I ctrl+LeftMouseClick on the label of that waveform
v*i

I have
interval start
interval end
Average
Integral

When I Press ctrl+LeftMouseClick on the label of Voltage only waveform
I have
interval start
interval end
Average
Rms

of the voltage only waveform


----------
How to view
RMS of the v*I waveform

like
interval start
interval end
Average
Rms

not
Interval start
interval end
Average
Integral

 

Hi SN2.
Please post your LTS asc file/
.
E

 

Alt+LeftMouseClickKey over inductor
gives for Power


Selecting voltage across Inductor gives



Need to view RMS of
V(N001,N002)*I(L1)
Waveform

not only for V(N002,N001) Waveform

 

Also the .asc file

 

hi SN2,
Is this what you asking?
RMS= V(N001,N002)*I(L1) *0.7071
E

 

I want to see
Average
RMS
The same as with the waveforms of Voltage and Current.

What is your definition of RMS for the power?
The average RMS value of the voltage and the current are indeed non-zero, but the average (RMS) power of the inductor is zero, and that's what the simulation is showing, so what do you think you should see?

 

RMS= V(N001,N002)*I(L1) *0.7071

What is that equation supposed to represent, since it's not the power dissipated by the inductor?

 

Need to view RMS of
V(N001,N002)*I(L1)
Waveform

This is what he asked, this is what I posted, no mention, no mention of power in my post.

I am trying to determine what he is asking

 

This is what he asked, this is what I posted, no mention, no mention of power in my post.

Okay, I just didn't understand why you would post an equation that has no useful technical meaning.
It seems apparent, that he doesn't understand the meaning of RMS when it comes to power.

 

How to view RMS value of this waveform

What is the command

 

Okay, I just didn't understand why you would post an equation that has no useful technical meaning.

I would say my post signature note best explains it, I am trying to understand the way he understands it and what he is really asking

You asked him and got no answer.

He has posted the same question in post #17.

 

How to view/calculate RMS value for this waveform
It is my question.


I have
Interval start
interval end
Average
Integral

not like I want
interval start
interval end
Average
Rms

 

Hi.

How to view the RMS value of waveform for power dissipation in Waveform Viewer.

LTspice v.17.0.36.0

I am able to view RMS value for Voltage and Current

Waveform separately by simply

Ctrl+LeftMouseClick on the

label of the waveform.

But when Press Ctrl+LeftMouseClick on the

label

of the Waveform of Power

dissipation (Obtained using Alt+Left Click over component) I can View only

Average and Integral Values.

Thank You.

You have to use .meas statements then view the results in the output log: