What is CVT calibration data?

Issue

User wants to know what CVT calibration data is.

Product

N, U, W, RL Series Reclosers

Environment

WSOS5

Cause

Voltage measurement accuracy in these recloser systems depends on device‑specific calibration values determined during factory testing.

Resolution

CVT calibration data is one of the key variables used by the voltage‑measurement algorithm in the recloser control system. These data values are:

• Determined during final routine factory tests.
• Stored in the SCEM board for the N, U, W, and RL series reclosers.
• Stored inside the ADVC3 controller for E‑series devices (paired during factory CVT calibration).

Because of natural manufacturing tolerances in electronic components and bushings, each bushing and SCEM combination has unique CVT calibration data.

Impact of SCEM Replacement

For N, U, W, and RL series reclosers, replacing the SCEM board may cause incorrect voltage readings.
To correct this:

1. Reload the latest CVT calibration data file into the device.
2. Use the Calibration menu in WSOS5 to fine‑tune voltage measurement.
3. Follow the on‑site CVT Calibration procedure for detailed steps.

Proper loading and calibration ensure accurate voltage measurement after hardware replacement.

Released for: Schneider Electric Canada