Question

is there any difference b/w optical current transformer and optical current transduer...pls help!! is there any difference b/w optical current transformer and optical current transduer...pls help!! @MIT 8.02 Electric…

Answer 1

yes optical current transformer maesures current but optical current transducer converts photon to electron

Answer 2

A transformer can be used to transfer current from one circuit to another. A transducer is a device that converts energy.
Both can be used for measurement, it depends on the scale of the signal. Lets say you have a big power cable carrying 50A, you can use an optical current transformer to convert this to an industry standard 4-20mA signal which will have very little effect on the current in your power cable.
The reason it is optical is to provide isolation. There is no electrical connection between the power circuit and the measuring signal circuit, this prevents an fault causing a dangerously high current going into your instrumentation.
An optical current transformer will have in it two transducers, one to convert the 50A to an optical signal, and then another to convert the optical signal back into your 4-20mA current.

Answer 3

On the left there are a low number of coils to pick up a small inductance driving a light emitting diode. On the right is a optically variable resistor being driven by its own isolated 10v.
Sorry it's a really bad drawing, if you wiki "optical isolator" you'll probably find a better pic.
Of course there are many other examples. I have an app on my Android that uses the camera flash light as a pulse oximeter. Basically it shines a light through your finger and measures how opaque or translucent it is. When your heart beats it pushes fresh oxigenated blood through your finger that lets through a different amount of light. My phone is able to measure this change in light from the fluctuation in overall brightness on the camera image - and there you have it an optical current transducer on your phone. :-)