AS 61869.5:2021 Instrument transformers Part 5: Additional requirements for capacitor voltage transformers (IEC 61869-5:2011 (ED 1.0) MOD).
This part of IEC 61869 applies to new single-phase capacitor voltage transformers connected between line and ground for system voltages Urn  72,5 kV at power frequencies from 15 Hz to 100 Hz. They are intended to supply a low voltage for measurement, control and protective functions.
The capacitor voltage transformer can be equipped with or without carrier-frequency accessories for power line carrier-frequency (PLC) application at carrier frequencies from 30 kHz to 500 kHz.
The base requirements for coupling capacitors and capacitors dividers are defined in
IEC 60358. The transmission requirements for coupling devices for power line carrier (PLC)
system are defined in IEC 60481.
The measurement application includes both indication measuring and revenue measuring.
NOTE 501 Diagrams of capacitor voltage transformer to which this standard applies are given in Figures 5A.1 and
5A.2.
2 Normative references
Clause 2 of IEC 61869-1:2007 is applicable with the following additions:
IEC 61869-1:2007, Instrument transformers — Part 1: General requirements
IEC 60038 ed7.0 (2009-06) — IEC standard voltages
IEC 60060-1, High-voltage test techniques — Part 1: General definitions and test requirements
IEC 60050-436, International Elect rot echnical Vocabulary (1EV) — Chapter 436: Power capacitors
IEC 60050-601, International Electrotechnical Vocabulary (1EV) — Chapter 601: Generation, transmission and distribution of electricity — General
IEC 60050-604, International Electrotechnical Vocabulary (1EV) — Chapter 604: Generation, transmission and distribution of electricity — Operation
IEC 60358, Coupling capacitors and capacitor dividers
IEC 60481, Coupling devices for power line carrier systems
3 Terms and Definitions
For the purpose of this document, the terms and definitions of IEC 61869-1 apply with the following additions:
General definitions
3.1.501
capacitor voltage transformer
CVT
voltage transformer comprising a capacitor divider unit and an electromagnetic unit so designed and interconnected that the secondary voltage of the electromagnetic unit is substantially proportional to the primary voltage, and differs in phase from it by an angle which is approximately zero for an appropriate direction of the connections.
[IEC 60050-321 :1986, 321-03-14, modified]
3.1.502
measuring voltage transformer
voltage transformer intended to transmit an information signal to measuring instruments, integrating meters and similar apparatus
[IEC 60050-321:1986 , 321-03-04 modified]
3.1.503
protective voltage transformer
voltage transformer intended to transmit an information signal to electrical protective and control devices
[IEC 60050-321:1986, 321-03-05]
3.1.504
secondary winding
winding which supplies the voltage circuits of measuring instruments, meters, protective or control devices
[IEC 60050-321:1986, 321-01-07 modified]
3.1.505
residual voltage winding
winding of a single-phase capacitor voltage transformer intended, in a set of three singlephase transformers, for connection in broken delta for the purpose of producing a residual voltage under earth-fault conditions.AS 61869.5 pdf download.