GPI GPI-ZL21R Instruction Manual

GPI-ZL21R

Laser Plummet

INSTRUCTION MANUAL

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Thanks for your trust on our product!

GPI-ZL21R laser plummet is precision surveying instrument. In order to get
maximum use of the features of you new product we recommend that you read
the manual in details.

The laser class of GPI-ZL21R is 2, please
don't stare into beam. At the same time, it is
safe for user to observe laser from eyepiece.

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Content

1. Applications and functions…………………………………………………….3

2. Main specifications……………………………………………………………4

3. Nomenclature of parts…………………………………………………………6

4. Operation………………………………………………………………………8

4.1 Setting, leveling and centering.....................................................................8

4.2 Aim.............................................................................................................11

4.3 Upward…………………………………………………………………...12

4.4 Measuring vertical outline………………………………………………..13

4.4.1 Optical measurement……………………………………………...13

4.4.2 Laser measurement………………………………………………..15

4.5 Transfer on vertical direction…………………………………………….14

5. Battery………………………………………………………………………..16

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1. Applications and functions

Straight direction and centralized energy are laser's characters, GPI-ZL21R, add
two laser diode bases on optical plummet, one laser beam through telescope. The
other laser beam are directed down through the plummet, it is easy to locate a
given reference point. The design ensure laser beam and telescope axis on same
center, same axis and same focus. There will be a red laser spot on the target
which you aimed. It is safe for user to observe laser from eyepiece. And laser
target makes your work more directly and convenient. Otherwise, there is a laser
target sheet as standard accessories; it is more convenient for measurement. It is
easy to measure with horizontal circle. The design is portable and stable. It can
be used in measuring small horizontal deviation, transfer on vertical direction,
measuring the object's outline. It is used widely in construction, industry
installing, engineering inspecting and distortion observation as well as many
others engineering survey.

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2. Specifications

Accuracy (Upward laser) ±2.5mm / 100M
Accuracy (Downward laser) ±1mm / 1.5M
Plate level sensitivity 20" / 2mm

Image Erect
Magnification 25 X
Field of view 1° 50'
Objective lens 36mm

Telescope

Focus 0.8m
Wave length 635nm
Laser class 2（IEC60825-1:2001-11）

Laser Range

Day≧I50m Night≧250m 100m

（visible from eyepiece）

Laser

(upward)

Output power < lmw, Adjustable

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Beam spot diameter ≦3mm / 50M
Error between telescope sight
axis and vertical axis

≦5"

Upward

Error between laser axis and
sight axis

≦5"

Wave length 635nm
Laser class 2（IEC 60825-1 :2001-11）
Working distance 0.5~80m
Output power < lmw, Adjustable

Laser

Plummet

Accuracy ± lmm / 1.5M

Battery

2pcs alkaline batteries or

rechargeable battery
Operation temperature -20°C ~ +50°C
Weight 2.8kg

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3. Nomenclature of parts

Fig. 1

Telescope focusing knob

Eyepiece
Eyepiece cover

Laser label

Circular level

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Plate level

Handle

Battery pack cover

Laser cover

Horizontal circle

Leveling screw

Objective cover

Fig. 2

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4. Operation

4.1 Setting, leveling and centering

Setting up the tripod on the measure-station point and
put the instrument on tripod head, then attach it to the
tribrach by the center screw. Adjust the height of
tripod to make eyepiece on same level with sight line.
Adjust tripod to make bubble centering. Switch on
the power and adjust the focusing knob to move laser
beam located the ground mark point.

Fig. 3

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Leveling

(1) Leveling with the circular level
By adjust leveling screws A and B,
position the bubble in the center of vial
（Fig.4）.
Adjust the leveling screw C, position the
bubble in the center of circle（Fig.5）.

Screw A

Screw B

Screw C

Screw A Screw B

Screw C

Fig. 4

Fig. 5

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(2) Leveling precisely with plate level
Loosen horizontal clamp screw, place the
plate level in parallel with a line joining
leveling screws A and B. Adjust the
leveling screw, position the bubble in the
center of plate level（Fig.6）.
Rotate the instrument 90∘ around the
vertical axis. Adjust the leveling screw C,
position the bubble in the center of plate
level.（Fig.7）. Repeat above steps until the
bubble remains in the center of plate level
while the instrument is rotated to any
position.

Screw A Screw B

Screw C

Fig. 7

Screw A Screw B

Screw C

Bubble

Plate level

Fig. 6

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Centering

(1) Switch on the laser switch, adjust the plummet focusing knob to move the
laser spot on the same horizontal plane with ground mark point.
(2) Loosen the tribrach clamp knob and move the instrument until the center
mark coincides with the ground mark point.
(3) Repeat leveling and (2) steps. Ascertain that the center of laser spot coincides
with the mark point when rotating alidade of instrument to any direction.
(4) At last clamp the tribrach again and switch off the laser to save battery
energy.

4.2 Aim

Place the laser target on the target.
Turn the eyepiece screw until the reticle cross-hair is clear. Then turn the
telescope focusing knob until the reflective sheet image is sharp and free from
parallax, i.e. there should be no apparent movement between cross-hairs and

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target as observer moves slightly. Otherwise, repeat the above steps until there is
no parallax.

4.3 Upward

(1) Optical plummet
Leveling the instrument, make the index points to zero graduation first, then read
out the first point. Then rotate the instrument through 180 and read out the
second point, take the average of these two points as final result. Repeat above
step could keep the accuracy of survey.
(2) Laser plummet
Switch on/off
Switch on the upward laser switch, one laser beam will emit through the
telescope, focus the laser spot on the laser target, read out the point. Repeat the
step as optical plummet, it could keep accuracy of survey. Use technique of laser
plummet is same with upward laser.

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4.4 Measuring vertical outline

Place a tripod around the object, and set up the
instrument on it, adjust the leveling screws until
the bubble always in the center of place level when
rotating instrument to any direction.

4.4.1 Optical measurement

(1) Turn the eyepiece until the reticle cross-hairs is
clear.
(2) Place a laser target close to object, and turn the
focusing knob until the laser target image is clear
on reticle. There should be no apparent movement
between cross-hairs and target when observer
moves slightly. If there IS parallax, adjust the
focusing knob slightly to remove it.
At last read out the value in the laser target.

Fig. 9

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(3) Move the laser target at regular intervals on vertical direction, and repeat the
(2) procedure. The vertical outline of object can be measured.

4.4.2 Laser measurement

(1) Turn the eyepiece until the reticle cross-hairs is clear.
(2) Place a laser target close to object, adjust the focusing knob until the laser
spot on laser target is the smallest, reading out the value.
(3) Move the laser target at regular intervals on vertical direction, and repeat the
(2) procedure. The vertical outline of object can be measured.

4.5 Transfer on vertical direction

In engineering or mining survey, in order to establish connection between the
ground and under the ground, the known azimuth or coordinate on the ground
need to be transferred to under the ground. It shows as following. As right figure
shows, the azimuth of line AB is known, point C and point D on the line AB as

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transfer points.
(1) Set up the instrument in the mine and tum
on the upward laser, move the instrument until
the laser collimating the point C.
(2) Turn on the downward laser, the laser spot
on the mine ground point E is related to point
C.
(3) Repeat (1) to collimate the point D and get
the point F as step (2).
(4) Connect the point E and point F, the
azimuth of line EF is same as line AB.
(5) Following the above procedure can achieve
other similar survey.

A

B

C

D

E

F

Fig. 10

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5. Battery

The power is 2pcs AA batteries or rechargeable battery. Replace the batteries:
The working time of 2pcs AA batteries is about 10 Hours.
Please replace the batteries when the laser light becoming dark. The operating
procedure is as follows: Push the fixing button on battery pack towards right and
open the pack cover, take out the old batteries and install the new ones according
to the indicating of positive and negative mark. Then cover it properly.

Giant Precision Instrument Co., Ltd.

International sales dep.

No.69, Anhe Rd., Zhonghe Dist., New Taipei City, Taiwan (R.O.C.) Zip:23576
Tel: [phone] Fax: [phone]