5.8 Levelling Equipment

 Barometric
 Laser

 Hand
172
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
456
148 cm
173
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
174
5.8.1 Spirit Levelling
Dumpy Levels
 Conventional Dumpy Level

 Telescope A rigidly attached to the level bar B

 Level tube sensitivity 20”/2mm div.
175
5.8.1 Spirit Levelling
Tilting Levels
(Keuffel & Esser)
 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 Instruments)
 Kern level more compact
 Same operation as K & E
 Eyepiece does not erect image
176
5.8.1 Spirit Levelling
Tilting Level

 Can rotate telescope and
level tube 180o about
longitudinal axis
Automatic Levels

 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.
(Leica)
177
(K & E)
(Leica)
178
5.8.1 Spirit Levelling
Automatic Levels
NA820, NA824 & NA828
Building construction and engineering
 A warning light in the field of view turns red if out of level extra security when measuring
[NA820]

 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
179
5.8.1 Spirit Levelling
Automatic Levels
Accuracy:
NA820
2.5"
Magnification:
20x
Shortest focus
distance:
0.5m/16 in
waterproof
specification:
focusing:
IP52
(splashproof)
fine
NA824
2.0”
NA828
1.5”
24x
28x
0.5m/16 in
0.7m/27 in
IP57
(submersible)
fine
IP52
(splashproof)
fine/coarse
180
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
181
5.8.3 Laser Levels
182
5.8.3 Laser Levels
183
5.8.3 Laser Levels
Topcon RL-S1A/S1B "Smart Rotating" Lasers
Model
Topcon RL-S1A
Topcon RL-S1B
Price
$2,795.00
$1,995.00
Nikon AL-50 Electronic Level
 AL-50 electronic level
 Range 1,650 feet
 Operating time is up to 80 hours
on alkaline batteries.
AL-50 Level w/ Sensor
w/ Rod Clamp
Remote display for sensor
Est. Price
$1,995.00
$495.00
$130.00
184
5.8.4 Digital Levels
[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.
185
 Replaces the Wild N3 precision level.
5.8.5 Hand Levels
Standard Hand Level
5x w/ Stadia, External Bubble Vial
Self Leveling Laser Hand
level
LeveLite®
 self-leveling pocket lasers
186
5.9 New Technologies
Horizontal Profilometer
Shape Accelerometer Array
IS – Liquid Leveling System
Multi-point leveling system
+/- 0.3 mm ?
187