ADE7880测小电流时,ADC输出的码值不稳定,波动幅度很大,怎么解决

1、ADE7880在没有电流输入时,也会有码值输出

2、ADE7880测小电流时,ADC输出的码值不稳定,波动幅度很大

怎么解决,谢谢!

Translation provided by Admin:

 

1, ADE7880 when no current input , there will be a code value output 2 , when the ADE7880 measure small current , unstable ADC output code value , large fluctuations   How to solve , thank you !


 
  • Hi Lyrain,

    I am not sure if you want to continue this discussion in Chinese or English but just so you know we do have a China EngineerZone website: 歡迎使用 | 中文技术支持.

    If you want to continue in English then I have a few questions:

    Please tell me a little more about the input, what is the size of the input when you mention small and large? The maximum input is +/-500mV PEAK.

    Do you have an example of how large the fluctuation is? Actual register values would help to understand this.

    What is the current sensor, is it a CT?

    Regards,

    Dlath

  • Hi Dlath,

    Thank you for your answer,whatever I use Rogowski Coil or CT as the Current Sensor, when the ADE7880 measure small current or no current input , read the regieter of Current ,I find two questions

    1.I can also get code value from Current  Regieter

    2.the  code value is unstable,it range 400 to 1359

     

    the follow is the current channal input

     

    Regards,

    Lyrian

  • Hi Lyrian,

    What you are measuring in the range of 400 to 1359 codes is just noise since it sounds like you have no current going through the current sensor. With full scale inputs (+/-500mV Peak waveform at IAP-IAN), the expected RMS codes is 3,766,572 codes.

    Regards,

    Dlath

  • Hi Dlath,

    Now I have the problem,What can I do to remove the noise? I have searched the questions about Current Register value in Engineer Zone,they all get a constant from current register !

  • Hi Lyrain,

    We recommend reading the register at least 50 times in a second for a 50Hz system and averaging in order to remove any ripple in the RMS measurement.

    Then if you could apply a signal to the input to take a look at the accuracy over the dynamic range because you will never be able to completely remove that noise to have the register show 0.

    Regards,

    Dlath