GB12526-1990

Specifications for long range electro-optical distance measurement

远程光电测距规范

GB 12526-1990 es una norma nacional china obligatoria vigente: Specifications for long range electro-optical distance measurement. Sector: Maquinaria. Enfoque: Métodos de ensayo. Entrada en vigor: 1 ago 1991.

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 applies to long-range electro-optical distance measurement using instruments with a nominal accuracy of no less than ±(5mm+1ppm·D) and a measurement range of no less than 15km. It covers side length measurements for national first- and second-order geodetic control networks, including baseline sides and traverse sides. It is mandatory for all surveying activities involving national first- and second-order geodetic networks in China. Other distance measurements of comparable precision may reference this standard.

Requisitos técnicos

The standard specifies comprehensive technical requirements for instrument verification, including frequency testing, additive constant determination, periodic error measurement, and optical centering checks. Instruments must undergo frequency verification before and after each observation period, with frequency deviation limits set at less than 1ppm. The additive constant must be determined before and after fieldwork, with a maximum discrepancy of ±6mm between two determinations. All instruments must pass verification before deployment in geodetic surveys. The standard also defines meteorological instrument requirements, including ventilation psychrometers (3-year calibration cycle) and aneroid barometers (annual calibration cycle), with specific comparison tolerances for field use. For distance measurement, the standard prescribes observation requirements including total observation sets (24 for first-order, 16 for second-order), minimum time segments, and maximum permissible discrepancies between observation sets. Environmental conditions such as line-of-sight clearance above ground and avoidance of electromagnetic interference sources are also specified.

Métodos de ensayo

Key testing methods include: frequency verification using calibrated frequency counters or color TV subcarrier comparison (per Appendix E); additive constant determination via segmented baseline comparison method on certified baselines of 600–2000m (per Appendix B); periodic error measurement using the platform method with precision rails (per Appendix F); observation value dispersion testing through 30+ consecutive readings (per Appendix A); and optical centering verification for both instrument-mounted and tribrach-mounted optical plummet systems (per Appendix C). Meteorological instrument comparison tests are also required at each station relocation.

Preguntas frecuentes

What types of instruments are regulated under GB 12526-1990?

GB 12526-1990 applies to electro-optical distance meters with a nominal accuracy of ±(5mm+1ppm·D) or better and a measurement range of at least 15km. Common instrument models referenced include the RM-III, AGA-8, and AGA-600 laser distance meters.

What are the key differences between first-order and second-order measurement requirements?

First-order measurements require 24 total observation sets across at least 3 time segments, while second-order measurements require 16 sets with either reciprocal observations or two different time segments. The permissible within-segment discrepancy after meteorological correction is 15mm for first-order and 20mm for second-order.

How does GB 12526-1990 relate to international standards?

GB 12526-1990 is a national standard specific to China's geodetic control network framework, referencing the Specifications for National Triangulation and Precise Traverse Survey (1974). It does not directly adopt ISO standards but establishes equivalent precision requirements for long-range electro-optical distance measurement in the Chinese geodetic context.

The summary above provides a high-level overview of GB 12526-1990. To ensure complete compliance for your surveying instruments and geodetic projects in the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 12526-1990 today to access all detailed parameters, calculation formulas, observation tables, and testing procedures.

Indicaciones de aplicabilidad

Tipo: Método
CCS: A76
ICS: 17.180.30
Organismo competente: Ministry of Natural Resources (Surveying, Mapping and Geography)
Comité técnico: National Technical Committee on Geographic Information of Standardization Administration of China