Maker

Leica (Wild), Heerbrugg, Switzerland

Model

NA 3000

Serial Number

91053

Dimensions

223 x 155 x 146 mm

Image

Description

This is the first model of a precision digital levelling instrument released by Leica (Wild Heerbrugg). It uses a mechanical compensator (+/- 0.4") as other automatic levels to keep the line of sight in the horizon. Electronic staff readings are possible from 1.8 m to 100 m. The distance measuring accuracy is 10-50 mm. The standard deviation of an one-kilometre double-run levelling with coded invar staffs (GPCL3/GPCL2) 0.4 mm. The staff readings can be displayed to 0.01 mm. The measuring time is for seconds. The instrument has on-board software for calibration and line levelling. The instrument has two GEB79 internal batteries (0.3 kg, NiCd 12V 500 mAh). The instrument can be operated from an external 12 V dc battery using an external battery cable Wild Type 439038.

Telescope magnification 24x, objective diameter 36 mm, field of view 3.5 m at 100 m, weight with one battery 2.5 kg.

The NA3000 allows data to be stored on removable solid-state memory cards. The instrument at hand includes two CMOS Wild GRM10 memory cards (64 k capacity, for 1120-2400 data blocks in GRE format, 74 x 60 x 10 mm, 70g).

The battery cable is attached to a y-cable that alows data transfers between the instrument and an external data recorder (such as the Wild GRE4).

The GEB batteries require a Wild GKL12 battery charger (240 x 100 x 75 mm, 2 x 0.2 A at 17 V dc). This charger can charge two batteries at the same time. Charging time is 14 h at 10-30 degrees Celsius.

A data reader is required to download the GRM10 data to a computer and for loading data from a computer to the GRM10 recording ('rec') module. Wild was supplying the GIF10 universal data reader (for parallel port on PC, power supply by personal computer or inbuild 9 V battery) and the GIS12 data reader (for RS232 port on IBM PC compatible computers, mains supply or internal 9 V battery) for PCs (running Microsoft DOS 2.11 or later. PC software supplied by Leica.

For mor information see:

Rüeger, 2003/2010, Monograph No. 18 (Electronic Surveying Instruments - A Review of Principles, Problems and Procedures, x+156 pages.

Rüeger. 1999. New Methods of Recording and processing Digital Levelling Data. The Australian Surveyor. 44(2): 165-173.

History & comments

cirka 1992. First digital level purchased by School.

Conservation

In padded plastic case (340 x 300 x 200 mm, 1.6 kg)

Condition

in mint condition

Remarks

Inv. No. 029607. Battery cells removed for conservation. Case contains 2nd GEB79 battery, 2nd GRM10 rec module, Allen key, rain cover, short manual

Dates

Catalogued in 2011 by JMR. Photo by JMR.