What is a current transducer? Current transducers provide a DC current or voltage output directly proportional to the AC input current. AC current transducers typically have a transformer input to isolate the transducer from the current input. Following the transformer are the electronics.
There are two types of AC current transducers:
Absolute average measuring, rms calibrated (or mean value measuring, rms calibrated).
These inexpensive transducers simply convert the AC input to DC and have the output calibrated to represent the root mean square (RMS) value for sine wave input. This type is very adequate for situations in which the current wave shape is not distorted. Any odd harmonic or discontinuity will introduce large error. Use the true RMS measuring type when distortion of a sine wave is present.
True RMS (root mean square) measuring
These transducers calculate the RMS value of the current input and provide a DC output directly proportional to the effective value of the current input. This type should be used whenever the current is distorted.
Ohio Semitronics, Inc. has a wide range of models available for various situations. Models are available with or without current transformer, with current transformers built in, and with split core current transformers.