172

5.8 Levelling Equipment

Barometric

Laser

Hand

173

5.8.1 Spirit Levelling

Precise Levels

2”/2mm sensitivity

Parallel plate micrometer

Invar matching level rods

148 000 cm

0 653 cm

148 653 cm

6 7

0.653 cm 148 cm

456

174

5.8.1 Spirit Levelling

Wye Levels Telescope tube rest in supports, called wyes (because

of shape)

Telescope can be rotated and turned end to end for

adjustment

Sunshade recommended

175

Dumpy Levels

5.8.1 Spirit Levelling

Conventional Dumpy Level

Telescope A rigidly attached to the level bar B

Level tube sensitivity 20”/2mm div.

176

5.8.1 Spirit Levelling Tilting Levels

Level bubble must be centered at time of

observation

Approx... level - bull’s eye bubble

Two eyepieces (image & split bubble

Observer can center bubble to within 0.3 mm

Kern level more compact

Same operation as K & E

Eyepiece does not erect image

(Keuffel & Esser)

(Kern Instruments)

177

5.8.1 Spirit Levelling

Tilting Level

Can rotate telescope and

level tube 180o about

longitudinal axis

(Leica)

Bull’s-eye bubble

Small triangular swinging prism in front of

eyepiece near bottom of telescope

Light on entering the objective lens passes

through the focusing lens and then through a fixed

prism. It then is reflected off the triangular prism

and passed through another fixed prism before it is

viewed.

Automatic Levels

178

(K & E)

(Leica)

179

5.8.1 Spirit Levelling Automatic Levels

NA820, NA824 & NA828

[NA820]

Building construction and engineering

A warning light in the field of view turns red if out of level -

extra security when measuring

Level bubble reflected in a mirror for comfortable viewing

operation in tough environmental and temperature conditions

Each of the three models offer a choice of features to suit

different types of leveling work.

the warning light turns red as

extra security

View through the level field of view

180

NA820 NA824 NA828

Accuracy: 2.5" 2.0” 1.5”

Magnification: 20x 24x 28x

Shortest focus

distance: 0.5m/16 in 0.5m/16 in 0.7m/27 in

waterproof

specification: IP52 IP57 IP52

(splashproof) (submersible) (splashproof)

focusing: fine fine fine/coarse

5.8.1 Spirit Levelling

Automatic Levels

181

5.8.2 Barometric Levels Aneroid Barometer

Used in surveys where precision of < 2

to 3 m is not required

Large barometer - good to 0.6 to 1 m.

Wallace & Tiernan Co. Inc.

Model FA-181071

Range -300 m to + 900 m

Graduations: 1.5 m

Readability 150 mm

Scale Length 30 in.

Dial Size 150 mm

Sensitivity1:8000

Accuracy 1:1000

Temp. Eff. 1:2000/10oC

Calibration Smithsonian Met.

Table No. 51

182

5.8.3 Laser Levels

183

5.8.3 Laser Levels

184

Topcon RL-S1A/S1B "Smart Rotating" Lasers

Model Price

Topcon RL-S1A $2,795.00

Topcon RL-S1B $1,995.00

5.8.3 Laser Levels

Nikon AL-50 Electronic Level

AL-50 electronic level Range 1,650 feet Operating time is up to 80 hours on alkaline batteries.

Est. Price AL-50 Level w/ Sensor $1,995.00 w/ Rod Clamp $495.00 Remote display for sensor $130.00

185

[NA2002]

Bar code level rod required

Engineers Digital Level

Accuracy in 1 km double run, 0.9mm to invar rod, 1.5mm to standard bar code

rod, 0.6m to 100m sighting range, distance accuracy 3-5mm/10m, 2 line x 8

character display, 64kb on board storage, GEB79 internal rechargeable battery,

RS232 port, 24x magnification, 360 degree graduation, endless fine drive.

Replaces the Wild N2 precision level.

NA3003 Precision Digital Level Accuracy in 1 km double run, 0.4mm to invar

rod, 1.5mm to standard bar code rod, 0.6m to 100m sighting range, distance

accuracy 3-5mm/10m, 2 line x 8 character display, 64kb on board storage, GEB79

internal rechargeable battery, RS232 port, 24x magnification, 360 degree

graduation, endless fine drive.

Replaces the Wild N3 precision level.

5.8.4 Digital Levels

186

5.8.5 Hand Levels

Standard Hand Level 5x w/ Stadia, External Bubble Vial

Self Leveling Laser Hand level LeveLite® self-leveling pocket lasers

187

5.9 New Technologies

Horizontal Profilometer

Shape Accelerometer Array

IS – Liquid Leveling System

Multi-point leveling system

+/- 0.3 mm ?