[SOLVED] ADE7758 Current measurement

[venkateshg]

Hi all,
I am using ADE7758 Energy meter Ic. In IC datasheet they given Typical Application Circuit Diagram. i followed that correctly. In current channel section, am giving the CT Input ,wave comes correctly(220mV, VPP) while checking the CRO. But when i am connecting the Netural to the IC ground. wave form not comes purely. that time peak to peak voltage goes 2.3V,VPP. Without neutral connecting time it come correctly.

please suggest me,if any changes in the circuit PDFwhich i attached.

 

[amit.kumar11]

Hi,

How you are generating 5V, from AC supply or from DC?

 

[venkateshg]

Hi . Input 230 to 12-0-12 transformer .then its output to regulator section and generating 5v to IC.

 

[amit.kumar11]

Hi,


I am doubting on you gnd connection. Please share your power schematics.

 

[venkateshg]

Re: ADE7758 with Both Power section

i posted the schematics, which is having both power section.

Input DC 12V- Am using 5V supply for MCU.
Input 12-0-12 TFR supply - For ADE7758 ic 5VA,5VD power.

 

[amit.kumar11]

Thanks,

could you please let me know in J11 connector what voltage you are giving, direct 230V mains or TFR o/p i.e 12V.

And i think there is no isolation between AGND and DGND. Since both are taken from TFR . Please check and let me know.

Check the value of R51,51 and R53, is it 8E? normally u have to use 1000:1 voltage divider.

 

[venkateshg]

1. J11 connector Direct 230V.
2. R51,R53 is now 680E .For Adjusting voltage max 500mV Vpp for the voltage channel pin.Now voltage is working fine.
3. In ADE7758 datasheet test circuit they given both AGND &DGND same ground. i attached the test circuit below for reference.

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But the current channel have same problem of Vpp increasing 160mv to 36.5v Vpp when given voltage to J11 connector Neutral connecting time....