Can I use CT instead of 350 micro Ohm Resistor to measure the current?

[suthar]

Can I used CT insted of 350 micro Ohm Resistor to measuring the current

Hello,
I am using ADE7757 Energy Measuring IC in that They are using the 350 micro Ohm Shunt Resistor. SO can i USE the CT instead of 350 micro Ohm?

Thank You

 

[betwixt]

Re: Can I used CT insted of 350 micro Ohm Resistor to measuring the current

You probably could as long as you limited the CT output voltage to 30mV but why would you want to do this? The idea of these devices is the cost is as small as possible so they minimize the cost of electricity meters, the CT alone may cost more than the rest of the circuit! Bear in mind you still need a direct connection to the power lines to measure the voltage so the isolation given by a CT is lost anyway.

Brian.

 

[smijesh]

Re: Can I used CT insted of 350 micro Ohm Resistor to measuring the current

You can replace by custom designed CT instead of shunt resistor. But no use
You can’t achieve 0.1% Error in 50Hz with CT,
Shunt resistor are very cheap and better for this IC but they are making power loss(I^2R), Low linearity (when temperature increased) and lack of isolation (Ground)