What is the Secondary Side Current in a Transformer-Based Energy Meter Design?

[harshasunder]

Hi
Im building an energy meter and I have a doubt about the voltage channel I am using to measure voltage. Basically there is a transformer that is connected between line and neutral and on the secondary side, there is voltage dividing resistor circuit to step down the voltage to the levels needed for the energy ic. The question is, how much current is flowing on the secondary side?The actual wires that I am measuring the energy from are using huge currents, 60 A etc but since there's no load connected to the transformer (Im not even using the transformer to power the Ic), there's only a current that depends on the resistors used for voltage dividing flowing on the secondary side right?
any comments would be welcome
Thanks
Harsha

 

[sophiecentaur]

I haven't understood what this "energy ic" does.
The current in your "secondary side" depends just on the resistors you choose to put there and the secondary voltage. This seems so obvious that I feel I must have missed something. Have I?
If you want to measure the power consumed then you also need a current transformer in series with your 60A cable.

 

[harshasunder]

hi
thanks for replying
the energy ic is an ade7752B analog device ic. It measures 3 phase power if you feed it voltage and current inputs from each phase. Yes, i know you need a current transformer, I just didnt mention it.
I wanted to be sure about the current on the secondary side and so the question. thanks for the reply, I am now more confident of my design.
thanks
Harsha