IEC 61869-14-2018 pdf download.Instrument transformers – Part 14: Additional requirements for current transformers for DC applications.
This part of IEC 61 869 provides all requirements specific to current transformers to be used in DC applications (DCCTs), whatever the technology used. The output signal can be analogue or digital.
It is applicable to newly manufactured current transformers used for measuring, protection and/or control applications in DC power systems with a rated voltage above 1 ,5 kV.
The general configuration of a single-pole low-power instrument transformer is described in Figure 601 of IEC 61 869-6:201 6.
The DCCTs intended for current measurement in the transistor branch of the VSC valve (referred to as CT4a and CT4b in Figure 1 403 and Table 1 402) are not covered by this document, and will be considered in a future revision.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
Clause 2 of IEC 61 869-6:201 6 is applicable, with the following additions and modifications:
IEC TS 6081 5-4:201 6, Selection and dimensioning of high-voltage insulators intended for use in polluted conditions – Part 4: Insulators for DC systems
IEC TS 61 245:201 5, Artificial pollution tests on high-voltage ceramic and glass insulators to be used on DC systems
IEC 61 869-6:201 6, Instrument transformers – Part 6: Additional general requirements for low- power instrument transformers
IEC 61 869-9:201 6, Instrument transformers – Part 9: Digital interface for instrument transformers
3 Terms and definitions
Clause 3 of IEC 61 869-1 :2007, of IEC 61 869-6:201 6 and of IEC 61 869-9:201 6 are applicable with the following additions and modifications.
3.1 General definitions
3.1 .1 401 instrument transformer for DC application instrument transformer intended to be used in DC applications with at least one of the following functions:
• measure DC current or DC voltage (with significant harmonics);
• withstand DC voltage.
3.1 .1 402 current transformer for DC application
DCCT instrument transformer for DC application in which the secondary signal, under normal conditions of use, is substantially proportional to the primary current
Note 1 to entry: The different applications are described in the introduction.
3.2 Definitions related to dielectric ratings
3.2.2 highest voltage for equipment
U m Definition 3.2.2 of IEC 61869-1:2007 is replaced by the following one: highest value of DC voltage for which the equipment is designed to operate continuously, in respect of its insulation as well as other characteristics that relate to this voltage
3.3 Definitions related to current ratings
3.3.1 401 DC overload current overcurrent occurring in an electric circuit, which is not caused by a short-circuit or an earth fault
Note 1 to entry: The DC overload current is specified by the customer in terms of value and duration.
[SOURCE: IEC 60050-826:2004, 826-1 1 -1 5, modified – “DC” added in the term and Note 1 to entry added.]IEC 61869-14 pdf download.