Test for accuracy of 800 kV Electronic Standard Voltage Divider manufactured by HAEFELY has been performed for CONDIS in November 2023 at LCOE High Voltage Lab. The Standard Capacitor was assembled previously by HAEFELY technicians at LCOE HV room, and the adjustment of the Electronic Standard Voltage Divider was performed by LCOE technicians before the calibration.

Measurement of ratio voltage error and phase displacement of the high voltage measuring system was performed for several rated ratios specified by the final customer with frequencies 50 Hz and 60 Hz. For each rated ratio the test for accuracy of the complete divider was performed applying from 2 % up to 190 % of rated primary voltage U_pr reaching the highest voltage level of 475 kV.

The LCOE accredited measurement uncertainty of 0.010 % for ratio error and 0.40 min for phase displacement was guaranteed during the calibration for all voltage levels.

Additionally, the calibration of the Electronic Voltage Divider was extended up to 700 kV performing a linearity test by direct comparison with LCOE approved HV capacitive measuring system, obtaining very good results and with measured ratio and phase errors by using this calibration method below the limits specified by CONDIS in all the voltage ranges.

LCOE is accredited by ENAC / ILAC to perform test for accuracy of voltage transformers according to ISO 17025 Std and is the Spanish Designated Institute in the CIPM MRA for high voltage magnitudes and calibrations. You can see LCOE accreditation scopes and the Calibration and Measurement Capability (CMC) in the following links:

• Technical scope of ISO 17025 accreditation, ENAC
• Calibration and Measurement Capability (CMC), CIPM MRA

More information about this publication www.lcoe-hv.com

• Tomás García tgarcia@ffii.es
• Paula Cid paula.cid@ffii.es