GB14050-2008

Types and safety technical requirements of system earthing

系统接地的型式及安全技术要求

GB 14050-2008 es una norma nacional china obligatoria vigente: Types and safety technical requirements of system earthing. Sector: Electrónica. Enfoque: Seguridad de productos. Entrada en vigor: 1 ago 2009.

La aplicabilidad depende del alcance del producto, la vía de certificación, los avisos de la autoridad competente y las reglas de transición. Solicite una traducción o verifique la fuente antes de usar esta ficha en una decisión de cumplimiento.

Resumen de cumplimiento

Este resumen está disponible por ahora solo en inglés.

Alcance y aplicabilidad

This standard specifies the types and safety technical requirements for system earthing, aiming to ensure the safety of personnel and equipment. It is specifically applicable to AC power grids with a nominal voltage of 220/380 V. It is mandatory for electrical installations operating within these voltage limits in China. The standard categorizes systems into TN, TT, and IT configurations, covering industrial, commercial, and residential applications.

Requisitos técnicos

The standard defines three primary earthing system configurations: TN, TT, and IT systems, detailing their structural variations such as TN-S, TN-C, and TN-C-S. It mandates that protective devices must automatically disconnect power during faults to prevent touch voltages from exceeding safe limits. For TN systems, the standard specifies requirements for fault loop impedance and protective device characteristics to ensure safe disconnection times, typically not exceeding 0.4s for portable equipment and 5s for fixed equipment. For TT systems, it outlines the relationship between the earth resistance of exposed conductive parts and the operating current of protective devices. Residual current devices are generally required for TT systems unless earth resistance is exceptionally low. For IT systems, the standard requires the installation of insulation monitoring devices to issue warnings during a first fault, and specifies protective measures for second faults. Additionally, it mandates strict rules for main equipotential bonding and supplementary equipotential bonding, referencing GB 16895.3-2004 for conductor specifications.

Métodos de ensayo

The standard primarily outlines evaluation formulas and calculation methods rather than physical laboratory tests. It specifies the assessment of fault loop impedance in TN systems and the measurement of earth resistance relative to protective device operating currents in TT and IT systems. Compliance verification involves calculating disconnection times and verifying the sizing of protective conductors. It also references the installation and operational testing of residual current protective devices (RCDs) and insulation monitoring devices according to GB 13955.

Preguntas frecuentes

What products and systems are regulated under GB 14050-2008?

It applies to AC power grids with a nominal voltage of 220/380 V, categorizing system earthing into TN, TT, and IT systems.

Are there any significant updates from the previous version of GB 14050?

It replaces GB 14050-1993 by adding normative references, refining terminology like PEN conductors, and explicitly requiring residual current protection devices and main equipotential bonding where necessary.

How does GB 14050-2008 relate to international IEC standards?

It aligns closely with international IEC standards, such as IEC 60364-5-54, particularly regarding protective conductor sizing and equipotential bonding requirements.

The summary above provides a high-level overview of GB 14050-2008. To ensure complete compliance for your electrical installations and products entering the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 14050-2008 today to access all detailed parameters, formulas, and testing procedures.

Indicaciones de aplicabilidad

Tipo: Seguridad
CCS: K09
ICS: 91.140.50
Organismo competente: Ministry of Industry and Information Technology
Comité técnico: Ministry of Industry and Information Technology

Relaciones

Sustituye a:GB 14050-1993