Sokkia & Topcon RAB-Code Barcode Staff Grade Rods

Overview

The Sokkia & Topcon RAB-Code Barcode Staff Grade Rods are precision leveling staffs designed for use with Sokkia SDL and Topcon DL Series Digital Levels. Utilizing RAB-Code (Random Bidirectional Code) technology, these staffs allow compatible digital levels to automatically measure staff heights and distances, reducing manual reading errors and improving measurement consistency.

Available in multiple lengths, materials, and configurations, these barcode staffs are suitable for professional surveying, construction leveling, geodetic measurements, and elevation monitoring. Choose from durable fiberglass and aluminum models for general field applications or high-precision Invar staffs for demanding leveling projects requiring exceptional accuracy and dimensional stability.

Key Features

• Sokkia & Topcon Compatibility: Designed for compatible Sokkia SDL and Topcon DL Series Digital Levels.

• RAB-Code Technology: Enables automatic digital height and distance measurements, reducing manual reading errors.

• Multiple Lengths: Available in 2 m, 3 m, 4 m, and 5 m configurations.

• Multiple Materials: Choose from fiberglass, aluminum, and precision Invar construction.

• High-Precision Invar Staffs: BIS20 and BIS30 models offer a low linear thermal expansion coefficient of 1 ppm/°C for precision leveling.

• Dual-Sided Graduations: Select models feature conventional metric or imperial graduations on the reverse side.

• Field-Ready Construction: Fiberglass and aluminum models provide practical options for everyday surveying and construction applications.

• Portable Designs: Telescoping fiberglass models are available in three- and four-section configurations for easier transportation and storage.

Available Models

BGS Series – Fiberglass Barcode Staffs

Designed for general surveying, construction leveling, and elevation measurements, the BGS Series offers durable fiberglass construction with RAB-Code graduations.

210154400 – BGS40 | 4 m Fiberglass Barcode Staff

• Length: 4 m (13.12 ft)

• Material: Fiberglass

• Sections: 3

• RAB-Code measuring face

• Metric graduations on reverse side

210154500 – BGS50 | 5 m Fiberglass Barcode Staff

• Length: 5 m (16.40 ft)

• Material: Fiberglass

• Sections: 4

• RAB-Code measuring face

• Metric graduations on reverse side

210154510 – BGS50G3 | 5 m Fiberglass Barcode Staff

• Length: 5 m (16.40 ft)

• Material: Fiberglass

• Sections: 4

• RAB-Code measuring face

• Feet, tenths, and hundredths graduations on reverse side

• Suitable for crews requiring imperial conventional measurements

BAS Series – Aluminum Barcode Staffs

210164300 – BAS55 | 5 m Aluminum Barcode Staff

• Length: 5 m

• Material: Aluminum

• RAB-Code graduations for compatible digital levels

• Alternative to fiberglass construction for general leveling applications

BIS Series – High-Precision Invar Barcode Staffs

The BIS Series is designed for high-accuracy leveling applications where temperature stability and measurement repeatability are particularly important. Invar construction minimizes dimensional changes caused by temperature fluctuations, making these staffs well suited for geodetic leveling, settlement monitoring, and precision engineering surveys.

BIS20 | 2 m Invar Barcode Staff

• Length: 2 m (6.56 ft)

• Material: Invar

• Linear thermal expansion coefficient: 1 ppm/°C

• RAB-Code graduations for precision digital leveling

• Suitable for high-accuracy elevation and control surveys

BIS30 | 3 m Invar Barcode Staff

• Length: 3 m (9.84 ft)

• Material: Invar

• Linear thermal expansion coefficient: 1 ppm/°C

• RAB-Code graduations for precision digital leveling

• Extended measuring length for high-precision surveying and monitoring applications

RAB-Code Technology for Accurate Digital Leveling

RAB-Code (Random Bidirectional Code) technology allows compatible Sokkia SDL and Topcon DL digital levels to electronically identify the staff markings and calculate height and distance measurements.

Unlike conventional leveling staffs that require manual readings through a telescope, RAB-Code staffs allow measurements to be captured electronically, helping reduce transcription errors and improving measurement efficiency.

The system is especially useful for repetitive leveling operations, benchmark transfers, and projects requiring consistent elevation measurements.

High-Precision Leveling with BIS20 and BIS30 Invar Staffs

For applications requiring greater precision than conventional fiberglass staffs, the BIS20 and BIS30 offer superior dimensional stability through their Invar construction.

Both models feature a linear thermal expansion coefficient of 1 ppm/°C, helping minimize measurement variations caused by changes in temperature.

When used with the Topcon DL-501 Digital Level, either the BIS20 or BIS30 supports a leveling accuracy of 0.3 mm per kilometer of double-run leveling, compared with 1.0 mm/km using a compatible BGS fiberglass staff.

These staffs are ideal for precision leveling applications such as deformation monitoring, vertical control networks, settlement surveys, and engineering projects with strict elevation tolerances.

Actual leveling accuracy depends on the digital level model, staff type, and measurement conditions.

Dual-Sided Graduations for Digital and Conventional Measurements

Select RAB-Code staffs feature graduations on the reverse side, allowing operators to perform both electronic and conventional leveling measurements.

• BGS40 and BGS50: RAB-Code measuring face with metric graduations on the reverse side.

• BGS50G3: RAB-Code measuring face with feet, tenths, and hundredths graduations on the reverse side.

This flexibility makes the BGS Series a practical choice for surveying crews using both digital and conventional optical leveling instruments.

Applications

• Digital Leveling: Automatic height and distance measurements using compatible Sokkia SDL and Topcon DL digital levels.

• Construction Surveying: Elevation checks, grading verification, and site control measurements.

• Precision Geodetic Leveling: High-accuracy elevation transfer using BIS Series Invar staffs.

• Settlement and Deformation Monitoring: Monitoring vertical movement in buildings, bridges, foundations, and other infrastructure.

• Benchmark Establishment: Establishing and maintaining reliable vertical control points.

• Engineering Surveys: Accurate leveling for civil engineering, transportation, and infrastructure projects.

Sokkia & Topcon Digital Level Compatibility

RAB-Code barcode staffs are designed for use with compatible digital levels in the Sokkia SDL Series SDL1X, SDL30, SDL50, and Topcon DL Series, including instruments such as the Topcon DL-501, DL-502, and DL-503.

Staff construction and model selection can affect the achievable leveling accuracy. Fiberglass models provide practical performance for general surveying and construction, while BIS20 and BIS30 Invar staffs are recommended for precision leveling applications.

Professional Surveying Equipment from Absolute Accuracy

Absolute Accuracy supplies professional Sokkia and Topcon surveying equipment, digital levels, barcode staffs, and leveling accessories. Our team can help you select the appropriate RAB-Code staff based on your digital level model, required accuracy, and surveying application.