Current Transfomers
The WattsOn transducer is unique in that it can be configured to work with a variety of current transformer (CT) types. It can be ordered to work with industry standard 5A, 333mV or mA output type CTs.
Each CT type has pros and cons, and it is advisable to read the application note discussing in detail the differences of the various CT types.
http://www.elkor.net/pdfs/AN0305-Current_Transformers.pdf
The most universal meters are the 5A and 333mV types, since the CT can be chosen after the meter is selected to match the full scale requirement of the system.
In the case of the mA output CTs, the meters must be ordered for a given CT and full scale current. Once this calibration is defined, it cannot be changed in the field. However, mA CTs have distinct advantages, such as higher accuracy, high immunity to electrical noise, smaller size and lower cost. For these reasons, Elkor recommends the use of mA CTs when possible. For maximum accuracy, solid core CTs will always out-perform split core models.
Each CT type has pros and cons, and it is advisable to read the application note discussing in detail the differences of the various CT types.
http://www.elkor.net/pdfs/AN0305-Current_Transformers.pdf
The most universal meters are the 5A and 333mV types, since the CT can be chosen after the meter is selected to match the full scale requirement of the system.
In the case of the mA output CTs, the meters must be ordered for a given CT and full scale current. Once this calibration is defined, it cannot be changed in the field. However, mA CTs have distinct advantages, such as higher accuracy, high immunity to electrical noise, smaller size and lower cost. For these reasons, Elkor recommends the use of mA CTs when possible. For maximum accuracy, solid core CTs will always out-perform split core models.