Re:interfacing Current transformer with microconroller(XMC1200)

[prathibhachelsi]

Re:interfacing Current transformer with microconroller(XMC1200)

Hi i found very useful information in this blog,As i am doing a project in which we connected current transformer to the microcontroller as ADC channel ,I am unable to fetch the reading of CT,As i am using 12-bit ADC some times i will get count of ADC as 2965,1837,750,32,78,i am not understanding what is these changes,i have connected 2 relays in that defaultly only second relay output is coming,for 1st relay
condition,As per my reuirement if adc count>1638 relay2 to be on,<2v relay1 to be on,but for both the cases relay2 is on when i check the same conditions with LED'S as per ADC Count,When i am doing same with relays this sort of changes happening like for any condition relay2 responding,many changes coming in CT ,Kindly help in hardware/coding need to change any thing ,i am working on hours on it please suggest me

 

[KlausST]

Re: interfacing Current transformer with microconroller(XMC1200)

Hi,

a schematic could help to understand your problem.

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A passive CT only works with AC. DC is not possible.

AC means alternating current. Alteranting means it changes.

Often AC is sinusoidal. If you do an AD conversion on a sinsoidal voltage you may get results ranging from negative peak to positive peak voltage.

For example: doing conversions on an 230V AC signal gives values from -325V ... +325V.


Klaus