GB/T 10963.3-2025Electrical accessories - Circuit-breakers for overcurrent protection for household and similar installations - Part 3: Circuit-breakers for DC operation (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents".

Drafting.

This document is Part 3 of GB/T 10963 "Electrical Accessories - Overcurrent Protection Circuit Breakers for Household and Similar Applications".

GB/T 10963 has published the following parts.

---Part 1: Circuit breakers for AC;

---Part 2: Circuit breakers for AC and DC;

---Part 3: Circuit breakers for DC applications.

This document replaces GB/T 10963.3-2016 "Overcurrent protection circuit breakers for household and similar applications - Part 3: DC".

Compared with GB/T 10963.3-2016, the main technical changes in "Circuit Breakers" are as follows, except for structural adjustments and editorial modifications.

---The rated voltage has been changed to not exceed 440V (see Chapter 1 and 5.3.1);

---The terminology and definition of critical current have been removed (see 3.2.15 in the 2016 edition);

---A new classification has been added for three-pole circuit breakers with two protective poles and one non-polarized protective M pole (see 4.2);

---Added mechanical and electrical life testing for three-pole circuit breakers with two protective poles and one non-polarized protective M pole.

Short-circuit verification (see 8.1.2, 9.11, and 9.12);

---Product categories and verification at ambient air temperatures of -25°C to 40°C have been removed (see 2016 version).

4.9, 8.6.3.2 (2016 version), and 9.10.4.2 (2016 version).

---The instantaneous tripping characteristic requirements have been changed (see 4.7, 5.3.4, and 9.10.3);

---The time constant category has been removed; time constant requirements are now specified separately in the test requirements (see sections 4.7, 9.10.3.1, and 2016 edition).

(9.11.1 and 9.12.5).

This document is equivalent to IEC 60898-3:2022 "Electrical accessories for overcurrent protection circuit breakers in household and similar locations - Part 3." Circuit breakers for DC power.

The following minimal editorial changes have been made to this document.

---The incorrect citation "9.12.9.1" in the original text has been corrected to "9.12.9.2" (see 9.12.9.3);

---The incorrect citation "9.13.2.1" in the original text has been corrected to "9.13.2.2" (see 9.13.2.1);

---The incorrect reference "9.10.2" in Appendix B, Table B.4, Note a is corrected to "9.10.3" (see Appendix B, Table B.4);

---The incorrect reference "9.5.1" in Appendix J Table J.3 Note b is corrected to "9.5.2" (see Appendix J Table J.3).

Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents.

This document was proposed by the China Electrical Equipment Industry Association.

This document is under the jurisdiction of the National Technical Committee on Standardization of Low Voltage Electrical Appliances (SAC/TC189).

Introduction

GB/T 10963 "Electrical Accessories - Overcurrent Protection Circuit Breakers for Household and Similar Applications" is a guideline for household and similar applications in my country.

The important series of standards for overcurrent protection circuit breaker products are proposed to consist of three parts.

---Part 1: Circuit Breakers for AC Systems. The purpose is to specify the performance requirements and testing procedures for circuit breakers used in AC systems.

Product requirements such as methods.

---Part 2: Circuit Breakers for AC and DC Systems. The purpose is to specify circuit breakers suitable for use in both AC and DC systems.

Product requirements, including performance requirements and testing methods.

---Part 3: Circuit Breakers for DC Systems. The purpose is to specify the performance requirements and testing procedures for circuit breakers used in DC systems.

Product requirements such as methods.

Electrical accessories for overcurrent protection in household and similar applications Circuit Breakers Part 3: Circuit Breakers for DC

1 Scope

This document applies to applications with a rated DC voltage not exceeding 440V, a rated current not exceeding 125A, and a rated short-circuit capacity not exceeding 10000A.

DC circuit breakers.

These circuit breakers are used to protect building wiring from overcurrent and for similar purposes; they are designed for use by untrained personnel.

It is usable and requires no maintenance.

The circuit breakers described in this document are intended for use in pollution level 2 environments.

The circuit breaker in this document has an isolation function.

The circuit breakers described in this document are suitable for use in TN and TT systems, and may be applicable to IT systems under special circumstances.

This document also applies to circuit breakers with several rated currents, provided that the current is changed from one rated value to another during normal operation.

The rated instrument is inaccessible and its rated value cannot be changed without tools.

This document is not applicable to.

---Circuit breaker to protect the motor;

---A circuit breaker whose setting current can be adjusted by a device accessible to the user.

For protection ratings higher than IP20 in IEC 60529, and for applications in harsh environments (e.g., excessive humidity, excessive heat, excessive cold, or dust).

Circuit breakers used in locations with sedimentation or in hazardous locations (such as places prone to explosion) may require special structures.

For environments with high levels of pollution, an enclosure with an appropriate level of protection should be used.

This document does not apply to AC-operated circuit breakers, the requirements of which are given in IEC 60898-1.

This document does not apply to circuit breakers that can be operated in both AC and DC modes; the requirements are detailed in IEC 60898-2.

The circuit breakers applicable to this document have high resistance to accidental tripping, whether caused by inrush current from electronic loads or circuits.

This was caused by the switching operation in the middle.

Note. Based on their tripping and installation characteristics, circuit breakers within the scope of this document can also be used for electric shock protection in fault conditions. (For electric shock protection) the scope of application is specified in the installation regulations.

This document contains all the requirements necessary to ensure that the type test results meet the operational performance requirements for this type of device.

This document also includes relevant details necessary to ensure the reproducibility of the test results.

Under short-circuit conditions, the guidelines for coordination between circuit breakers and other short-circuit protection devices (SCPDs) are provided in Appendix C.

Routine tests for revealing unacceptable changes in materials or manufacturing that may affect safety are described in Appendix G.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies.

This document.

GB/T 3956-2008 Conductors of cables (IEC 60228:2004, IDT) GB/T 5169.11-2017 Fire Hazard Testing of Electrical and Electronic Products - Part 11: Basic Test Methods for Glow Wire/Hot Wire Glow wire flammability test method (GWEPT) (IEC 60695-2-11:2014, IDT) GB/T 16935.1-2023 Insulation Coordination of Equipment in Low-Voltage Power Supply Systems - Part 1: Principles, Requirements and Tests