GB/T 40820-2021 Active

This document specifies the classification, characteristics, marking, conditions for use and installation, structural and operational technical requirements, and corresponding tests for DC residual current detection devices (RDC-DD) used for Mode 3 charging of electric vehicles.
This document applies to DC residual current detection devices (hereinafter referred to as RDC-MD or RDC-PD) permanently connected to AC charging stations for electric vehicles (Mode 3 charging according to IEC 61851-1 and IEC 60364-7-722), with a rated voltage not exceeding 440 V AC, a rated frequency of 50 Hz, 60 Hz, or 50/60 Hz, and a rated current not exceeding 125 A.
Note 1: This document can also be used as a guide for devices with an AC voltage of 690 V, a rated frequency of 50 Hz, 60 Hz, or 50/60 Hz, and a rated current not exceeding 250 A.
RDC-DD is used to disconnect or trigger the disconnection of the electric vehicle's charging when a smooth DC residual current greater than or equal to 6 mA is detected.
Note 2: The value of 6 mA for the smooth DC residual current is selected to prevent affecting the correct operation of the upstream Type A or Type F RCDs.
This document includes two different types of DC residual current detection devices (RDC-DD) for Mode 3 charging of electric vehicles (see 4.1 Classification).
——RDC-MD (monitoring device); and
——RDC-PD (protection device).
This document applies to devices that can simultaneously detect DC residual current, compare the residual current value with the residual action current value, and initiate the disconnection circuit when the DC residual current exceeds 6 mA.
The RDC-PD specified in this document is suitable for isolation.
RDC-DD is intended for use in single-phase or multi-phase circuits in TN, TT, and IT systems.
RDC-DD is intended for use in fixed installations.
RDC-DD is only for AC circuits. The RDC-DD specified in this document is not suitable for bi