Missing pre-defined functions under data logger?

[Kirkhaan]

In the reference manual I see several RMS functions listed for the data logger:

However, in version 3.23.4 on my Linux machine I do not see them:

Anyone an idea where this delta is coming from?

I have a few high voltage differential probes hooked up to my ADP3450 and want to log the RMS value of the mains for a few hours.
 

 

 

Edited Monday at 06:29 PM by Kirkhaan
Corrected the image URL's

[attila]

Hi @Kirkhaan

You can add it from the Item tab or enter C#RMS as function, but RMS and AC are no more supported in operations.
I had to reimplement the background and remove these from operations to allow high update rates in Logger.

[Kirkhaan]

As always, thanks for your swift reply @attila!

Then I have to find another solution for logging the RMS AC mains voltage.

Is it possible to plot a measurement (e.g. as a math channel) in the oscilloscope mode? 
I realize that it cannot log for hours then, but its a good starting point for me to see how the AC RMS voltage trend develops over minutes.

[attila]

Hi @Kirkhaan

I just notice you can use (true)RMS and AC(rms) but have to increase the Samples option.

[Kirkhaan]

Thanks for digging further @attila. 
I'm going to check it out tomorrow!

[Kirkhaan]

@attila, already managed to do a check. It works, but I get too low voltage rating. See attached screenshots.

It is consistently measuring 180V in the Data Logger, while the RMS measurement in the oscilloscope mode shows 230V (correct value).
It does not matter which sample rate I choose. Probe settings are set to 200 X, so are correct. Any idea what I could be missing?

 

 

[attila]

Hi @Kirkhaan

Try setting the channel input in Logger also to low range, like it is in Scope with 200X 100V/div.
For ACRMS use C2AC

[Kirkhaan]

Hey @attila, I had to set it to 10kV and then it works (also Maximum did not work).

I checked on the scope and it indeed was related to a clipping signal. In scope mode the same 180V is measured with 20V/div.

Somewhat strange that the Maximum range does not work. Anyhow, I can proceed now. Thanks for helping me out!!

[attila]

Hi @Kirkhaan

Now I see you are using ADP3450, for BNC devices (ADP3X50, ADP2230) the low range is from 0.2V/div 2Vpk2pk and with 200x 40V/div 400Vpk2pk. For AD is 0.5V/div ...
The Maximum in Logger did not take in account the Attenuation setting. It is corrected for the software version.

[Kirkhaan]

Understood - thanks for closing the loop of understanding.