What is CVT calibration data?

FA352342

15 August 2022

Issue
User wants to know what CVT calibration data is

Product Line
N, U, W, RL series reclosers

Environment
WSOS5

Resolution
One of the variables used by the algorithm in voltage measurement scheme is CVT data.
 
CVT data are figures which are determined in one of the final routine tests in factory and stored in SCEM board of N, U, W, RL series. For E series, it is stored inside the ADVC3 controller which is paired with the switchgear at time of the CVT calibration tests are conducted.
 
 Due to manufacturing errors of electronic components and bushings, CVT data is unique to every bushing and SCEM (where installed) combination.
 
Therefore, for N, U, W and RL series replacement of SCEM may cause voltage readings to be incorrect. In such cases, voltage measurement can be recalibrated by first reloading the latest CVT data file, then adjusting voltage reading using the Calibration menu on WSOS software. Refer to the on-site CVT Calibration procedure for more information.
 
;