Measured rms value through Simulink with STM32F407 is varying very slowly after changing input?

I am using STM32F407 microcontroller with Simulink. After taking the input samples through ADC i convert it to voltage and then measure the rms value using RMS block in DSP system toolbox. I have used running rms for rms computation. I am getting the measured rms value at the LCD but when i remove the input i.e. 0V, the LCD or even LEDs do not respond instantaneously rather the value starts decreasing and gets to zero in almost minutes i.e. 4-5 min from 115V. I want help to understand what is the reason for this slow response in rms computation and is there any solution for it?

Answer 1

[nitish agarwal]

Hey, I am facing the same difficulty. I am using DRMS block. If u have rectified the problem then pls let me know

[muhammad saad malik]

use the rms block in dsp system toolbox with "entire input" as the selection preceded by a buffer with number of samples in one cycle as the value in first box. Leave the remaining boxes as it is.

Answer 2

[Ahmet yüksel]

Hey, I am facing the same difficulty. I am using DRMS block. If u have rectified the problem then pls let me know. how to solve this error. may you help me please

[muhammad saad malik]

use the rms block in dsp system toolbox with "entire input" as the selection preceded by a buffer with number of samples in one cycle as the value in first box. Leave the remaining boxes with their default values.