Riegl LD90-3 User manual

LASER DISTANCE AND LEVEL METER
LD90-3
USER'S MANUAL
Version 9/01 CE
Rev. 05-09-2001 (S 5.1)
Rev. 18-09-2001 (S 5.1)
Rev. 13-03-2002 (S 5.1)
Rev. 19-03-2002 (S 5.1)
Rev. 24-11-2005 (S 5.1)
Rev. 16-06-2006
24/06

© 2006 RIEGL Austria
All rights reserved.
No parts of this document may be reproduced in any form or by any means – graphic,
electronic, or mechanical, including photocopying, recording, taping, or information
storage and retrieval systems – without the written permission of RIEGL LMS.
Products that are referred to in this document may be either trademarks and/or
registered trademarks of the respective owner. RIEGL LMS makes no claim on these
trademarks.
While every precaution has been taken in the preparation of this document, RIEGL LMS
assumes no responsibility for errors or omissions within it, or for damages resulting from
the use of information contained in this document or for the use of programs and source
code that may accompany it. In no event shall RIEGL LMS be liable for any loss of profit
or any other commercial damage caused or alleged to have been caused directly or
indirectly by this document.
Text and data of this document are subject to change without notice.
The user is asked to excuse any technical inaccuracy or typographical error in this
document.
RIEGL Laser Measurement Systems GmbH
A-3580 Horn, Riedenburgstrasse 48, AUSTRIA,
Tel: [phone], Fax: [phone]
email: [email protected]
www.riegl.com
24/06

CONTENTS
1Short-form Description and Specifications............1
2Safety and Reliability .............................................11
3Preparing for Measurement...................................22
3.1 Mounting Instructions............................................................. 22
3.2 Preparing the Power Supply .................................................. 25
3.3 Fuse ....................................................................................... 26
3.4 Internal Grounding Scheme................................................... 26
3.5 Laser Safety Lock .................................................................. 27
3.6 Accuracy of Measurement ..................................................... 27
3.7 Short Guidance for a Fast Start-Up ....................................... 28
4What to Know for a Good Measurement .............. 29
4.1 Measurement Results ............................................................ 29
4.2 Selecting the Appropriate Program ....................................... 30
4.3 Measurement to Badly Reflecting Targets ............................ 31
4.4 Selective Measurement to Targets with Definite
Reflection Characteristics ...................................................... 31
5Data Communication via RS232/RS422................32
5.1 Communication Parameter .................................................... 32
5.2 Programming Mode / Measurement Mode ............................ 32
5.3 Data Format ........................................................................... 33
5.3.1 Data Format in Programming Mode............................... 33
5.3.2 Data Format in Measurement Mode .............................. 33
6Optional Analog Outputs....................................... 35
7Optional Switching Outputs .................................. 37
8Adjustment of Parameters.....................................39
8.1 Measurement Program - Range Measurement ..................... 39
8.2 Unit - Range Measurement.................................................... 39
8.3 Measurement Time and Resolution - Range
Measurement ......................................................................... 40
8.4 Speed Measurement ............................................................. 41
8.4.1 Speed Measurement Activation ..................................... 41
- I -

8.4.2 Unit - Speed Measurement ............................................ 41
8.4.3 Measurement Time - Speed Measurement ................... 41
8.5 Hold Time............................................................................... 42
8.6 Distance Offset (Adjustment of the Reference Plane)......... 42
8.7 Data String Format................................................................. 43
8.8 Serial Baud Rate, Parity and Separator ................................ 44
8.8.1 Baud Rate: ..................................................................... 44
8.8.2 Parity: ............................................................................. 44
8.8.3 Separator:....................................................................... 45
8.9 Serial Mode............................................................................ 45
8.10 Trigger Mode.......................................................................... 46
8.11 Parameter Query ................................................................... 46
8.12 Set User Parameters to Default............................................. 47
8.13 New Start ............................................................................... 48
8.14 Saving, Write to EEPROM ..................................................... 48
8.15 Quit Programming Mode........................................................ 48
8.16 Signal Amplitude Window ...................................................... 49
8.17 Analog Current Output - Adjustment (optional) ..................... 50
8.17.1 Setting the range value corresponding to 4mA
output ............................................................................. 50
8.17.2 Setting the range value corresponding to 20mA
output ............................................................................. 50
8.17.3 Analog current output - No target status value .............. 50
8.17.4 Analog current output – Error status value .................... 51
8.17.5 Analog current output – Warning status value............... 51
8.17.6 Analog current output - Message status value .............. 51
8.18 Analog Voltage Output - Adjustment (optional) ..................... 53
8.18.1 Setting the range value corresponding to 0 V
output ............................................................................. 53
8.18.2 Setting the range value corresponding to 10 V
output ............................................................................. 53
8.18.3 Analog voltage output - No target status value.............. 53
8.18.4 Analog voltage output – Error status value .................... 54
8.18.5 Analog voltage output – Warning status value ..............54
8.18.6 Analog voltage output - Message status value .............. 54
8.19 Switching Output - Adjustment (optional) .............................. 56
8.19.1 Setting the range value for changing output level to
low .................................................................................. 56
8.19.2 Setting the range value for changing output level to
high................................................................................. 56
8.19.3 Switching output - No target status value ...................... 57
8.19.4 Switching output - Error status value ............................. 57
8.19.5 Switching output – Warning status value ....................... 57
- II -

8.19.6 Switching output - Message status value ...................... 57
9Serial Control Commands in Measurement
Mode........................................................................59
9.1 Start Programming Mode....................................................... 59
9.2 Laser On ................................................................................ 59
9.3 Laser Off ................................................................................ 59
9.4 Trigger Measurement ............................................................ 59
9.5 Trigger of RS232/RS422-Data Output, RS232/RS422
Inquiry Mode .......................................................................... 60
9.6 Clear RS232/RS422 Inquiry Mode ........................................ 60
9.7 Start Self Check ..................................................................... 60
10 Command Summary............................................... 61
10.1 Commands in Programming Mode ........................................ 61
Commands in Measurement Mode................................................. 62
10.2 Commands in Programming Mode only for Instruments
with Optional Current, Voltage or Switching Output .............. 62
10.3 Status and Error Messages ................................................... 64
11 Pinning and Cables................................................ 65
11.1 Instruments without Optional Analog Output,
Instruments with Current Output Only ................................... 65
11.2 Instruments with Switching Output, Instruments with
Switching Output & Current Output & Voltage Output..........69
- III -

- IV -

Dear Customer!
We congratulate you on the purchase of the RIEGL LD90-3. You are
now the owner of a high quality, optoelectronic measuring instrument.
The instrument is easy to operate.
However, we would ask you to take the time to carefully work
through these operating instructions - especially the chapters 2
to 4- before using the instrument.
1 Short-form Description and Specifications
See next pages.
- 1 -

- 2 -

Accurate & dynamic measurement of distance and speed
Short high-energy infrared light pulses provide excellent interference immunity
Measurements are fast offering update rates as high as 200 Hz
Measurements can be taken through glass windows into sealed containers
Narrow measurement beam with very low divergence provides excellent spatial
resolution
Measurements can be taken to almost any surface regardless of the incident beam
angle or surface characteristics
Measurements are unaffected by the temperature of the material surface and of
temperature gradients in the medium between the sensor and the target surface
Excellent performance and reliability; lightweight and stable metal housing
Industrial distance and
speed sensing
Collision avoidance for
cranes and vehicles
Level measurement in silos
Laser altimeter
Sensor for ship docking
Key features
visit our webpage
www.riegl.com
- 3 -

An electrical pulse generator periodically
drives a semiconductor laser diode sending
out infrared light pulses, which are collimated
and emitted by the transmitter lens. Via the
receiver lens, part of the echo signal
reflected by the target hits a photodiode
which generates an electrical receiver
signal.
The time interval between the transmitted
and received pulses is counted by means of
a quartz-stabilised clock frequency. The
result is fed into the internal microcomputer
which processes the measured data and
prepares it for the various data outputs.
Principle of operation
Digital
interface
Semiconductor
diode laser
Transmitter lens Target
Receiver lens
Reflection
coefficient
ρ
Photodiode-
receiver
Micro-
computer
Time
measurement
unit
Analog-
output
(option)
9pole socket for RS232/RS422 data interface(1)
(2) LED "POWER ON"
(3) 10pole socket for power supply,
optional analog outputs, and
(4) Fuse holder
switching output
Mounting plates with 2xM6 threads(6)
(5) Rubber-armoured front and rear panel
on both sides of the instrument
(7b) Telescope (optional)
(7a) Mounting for aiming device (optional)
Receiver lens(8)
(9) Transmitter lens
Elements of operation and dimensional drawings
130
118
70 30
85
30 200
<100
76
1
4
5
7a
6
5
8
7b 9
3
2
RS232 / RS422
4-20mA
11 - 28 V DC
1 m - 150m
LD90-3100
RIEGL Laser Meas urement S
y
stems GmbH
A-3580 Horn AUSTRIA
Power supply:
Data output:
Meas.range:
Type:
- 4 -

General technical data LD90-3RIEGL
Information contained herein is believed to be accurate and reliable. However, no responsibility is assumed by
for its use. Technicaldata are subject to changewithout notice RIEGL
Data interfaces
RS232 & RS422 (selectable, standard for all types)
Baud rate selectable between 150 Bd and 19200 Bd,
further 38.4 kBd and 115.2 kBd
A data output options (not for all types)vailable
Analog current
Voltage output
Switching output
4-20 mA , not galvanically isolated,
resolution 16 Bit, linearity 1 of full scale
1)
‰
0-10 V , not galvanically isolated, resolution 12 Bit
2 x PNP transistor driver
built-in thermal and short-circuit protection
switching current 200 mA max.
switching voltage = supply voltage
1)
2)
Physical data
Dimensions
Weight
Protection class
200 x 130 x 76 mm (L x W x H)
approx. 1.5 kg
IP64
Aiming device (optional)
Telescope or red semiconductor-laser beampointer to be mounted
on top of the instrument
Power supply
Standard
Option 220 V AC
11-28 Volts DC, approx. 10 Watt
built-in protecting circuitry for
over-voltage and reverse polarity
external power supply module VNG95
Temperature range
Operation
Storage
-10 C to +50 C
-20 C to +60 C
oo
oo
1)
2)
Operating range selectable via serial interface
Switching points adjustable via serial interface
, A-3580 Horn, Austria
Tel.: [phone], Fax: [phone], E-mail: [e-mail]
RIEGL Laser Measurement Systems GmbH
RIEGL USA Inc.
, Orlando, Florida 32819, USA
Tel.: [phone], Fax: [phone], E-mail: [e-mail]
RIEGL Japan Ltd. , Tokyo 1640013, Japan
Tel.: [phone], Fax: [phone], E-mail: in[email protected]
www.riegl.com
- 5 -

LD90-3100HS general purpose distance meter
Measuring time (ms or s)
Statistical deviation (mm)
Resolution (mm)
±30
5ms
20
±20
10ms
20
±15
20ms
10
±10
50ms
10
±7
0.1
5
±5
0.2
5
±3
0.5
2
±2
1
2
4)
5) 6)
5)
High-Speed distance
meter for robotics applica-
tions, automatic anti-
collision systems, etc.
good, diffusely reflecting targets, 80% ≥
bad, diffusely reflecting targets, 10% ≥
Reflecting foil or plastic cat´s-eye reflectors
Accuracy
Divergence of the infrared measuring beam
50 mup to
> 1000 m
150 mup to
1.8 mrad
typically ±15 mm, in the worst case ±50 mm
LD90-3100HS
1)
1)
3)
2)
7)
Measuring range
depending on the reflection coefficient of the target
Minimum distance, typically 1 m
Eye safety class according to
IEC60825-1:1993+A1:1997+A2:2001
The following clause applies for instruments
delivered into the United States:
Complies with 21 CFR 1040.10 and 1040.11 except for deviations
pursuant to Laser Notice No. 50, dated July 26, 2001.
typical values for average conditions. In bright sunlight, the operational range is considerably
1)
4)
2)
3)
reflecting foil 3M 3000X or equivalent, minimum dimensions 0.45 x 0.45 m
2
shorter than under an overcast sky. At dawn or at night the range is even higher.
standard deviation, plus distance depending error 20 ppm
≤
depending on measuring time
5)
6)
7)
chosen automatically by the internal microprocessor
1 mrad corresponds to 10 cm beamwidth per 100 m of distance
selectable via RS232/RS422
Information contained herein is believed to be accurate and reliable. However, no responsibility is assumed by
for its use. Technical data are subject to change without notice. RIEGL
The program FAST enables the quickest
possible measurement at undisturbed
conditions simply by averaging the single-
pulse distance values which are acquired
within the selected measuring time.
The program STANDARD provides a very
useful clutter suppression: occasional echo
signals caused not by the target itself but by
backscattering of particles between target
and instrument (e.g. clouds of material in a
dusty silo, or raindrops and snowflakes in
free air) are eliminated and not taken into
account.
The program MAXIMUM DISTANCE is
optimized for undisturbed level measure-
ments in a silo at the cost of a slightly higher
acquisition time.
The program MINIMUM DISTANCE is ideal
for measurements to small targets which are
not easy to aim at, as it eliminates
background echoes.
Selectable data processing modes
General technical data and dimensions as given in our general data sheet LD90-3 series.
Data sheet LD90-3100HS, 08/06/2006RIEGL
CLASS 1
LASER PRODUCT
, A-3580 Horn, Austria
Tel.: [phone], Fax: [phone], E-mail: [e-mail]
RIEGL Laser Measurement Systems GmbH
RIEGL USA Inc.
, Orlando, Florida 32819, USA
Tel.: [phone], Fax: [phone], E-mail: [email protected]
RIEGL Japan Ltd. , Tokyo 1640013, Japan
Tel.: [phone], Fax: [phone], E-mail: [e-mail]
www.riegl.com
- 6 -

typical values for average conditions. In bright sunlight, the operational range is considerably
1)
4)
2)
3)
reflecting foil 3M 3000X or equivalent, minimum dimensions 0.45 x 0.45 m
2
shorter than under an overcast sky. At dawn or at night the range is even higher.
standard deviation, plus distance depending error 20 ppm
≤
selectable via RS232/RS422
depending on measuring time
5)
6)
7)
chosen automatically by the internal microprocessor
1 mrad corresponds to 10 cm beamwidth per 100 m of distance
LD90-3300 long-range distance meter
good, diffusely reflecting targets, 80% ≥
bad, diffusely reflecting targets, 10% ≥
Reflecting foil or plastic cat´s-eye reflectors
Accuracy
Measuring time (ms or s)
Measuring range
Speed measurement:
Distance measurement:
Statistical deviation (cm)
Accuracy
Resolution (cm)
Measuring time, typically
Divergence of the infrared measuring beam
120 mup to
> 1000 m
400 mup to
±0.5 m/s
0 to ±30 m/s
0.5 s
1.6 mrad
typically ±50 mm
LD90-3300
1)
1)
4)
3)
2)
5) 6)
4)
7)
5)
Measuring range
depending on the reflection coefficient of the target
Minimum distance, typically 2 m
±10
10ms
10
±7
20ms
10
±5
50ms
5
±3
0.1
5
±2
0.2
2
±1.5
0.5
2
±1
1
1
±0.7
2
1
Powerful distance and
speed meter for long
ranges and/or badly
reflecting targets:
Height-of-flight mea-
surements on planes or
helicopters, tide gage in
hydrography, level
measurement in large
coal silos, etc.
good, diffusely reflecting targets, 80% ≥
bad, diffusely reflecting targets, 10% ≥
Reflecting foil or plastic cat´s-eye reflectors
Accuracy
Measuring time (ms or s)
Measuring range
Speed measurement:
Distance measurement:
Statistical deviation (cm)
Accuracy
Resolution (cm)
Measuring time, typically
150 mup to
> 1000 m
500 mup to
±10
10ms
10
±7
20ms
10
±5
50ms
5
±3
0.1
5
±2
0.2
2
±1.5
0.5
2
±1
1
1
±0.7
±0.5 m/s
2
0 to ±30 m/s
1
0.5 s
typically ±50 mm
LD90-3300HR
1)
1)
4)
3)
2)
5)6)
4)
5)
Measuring range
depending on the reflection coefficient of the target
Minimum distance, typically 5 - 10 m
High-Range version of
LD90-3300 for use in
ship-docking systems,
for scanner applica-
tions, etc.
Divergence of the infrared measuring beam 1.6 mrad
7)
Eye safety class according to
IEC60825-1:1993+A1:1997+A2:2001
The following clause applies for instruments
delivered into the United States:
Complies with 21 CFR 1040.10 and 1040.11 except for deviations
pursuant to Laser Notice No. 50, dated July 26, 2001.
CLASS 1
LASER PRODUCT
Eye safety class according to
IEC60825-1:1993+A1:1997+A2:2001
The following clause applies for instruments
delivered into the United States:
Complies with 21 CFR 1040.10 and 1040.11 except for deviations
pursuant to Laser Notice No. 50, dated July 26, 2001.
CLASS 1
LASER PRODUCT
- 7 -

Information contained herein is believed to be accurate and reliable. However, no responsibility is assumed by
for its use. Technical data are subject to change without notice. RIEGL
Data sheet LD90-3300, 08/06/2006RIEGL
The program FAST enables the quickest
possible measurement at undisturbed
conditions simply by averaging the single-
pulse distance values which are acquired
within the selected measuring time.
The program STANDARD provides a very
useful clutter suppression: occasional echo
signals caused not by the target itself but by
backscattering of particles between target
and instrument (e.g. clouds of material in a
dusty silo, or raindrops and snowflakes in
free air) are eliminated and not taken into
account.
The program MAXIMUM DISTANCE is
optimized for undisturbed level measure-
ments in a silo at the cost of a slightly higher
acquisition time.
The program MINIMUM DISTANCE is ideal
for measurements to small targets which are
not easy to aim at, as it eliminates
background echoes.
Selectable data processing modes
General technical data and dimensions as given in our general data sheet LD90-3 series.
, A-3580 Horn, Austria
Tel.: [phone], Fax: [phone], E-mail: [e-mail]
RIEGL Laser Measurement Systems GmbH
RIEGL USA Inc.
, Orlando, Florida 32819, USA
Tel.: [phone], Fax: [phone], E-mail: [e-mail]
RIEGL Japan Ltd. , Tokyo 1640013, Japan
Tel.: [phone], Fax: [phone], E-mail: [e-mail]
www.riegl.com
- 8 -

LD90-3100HS-HT
Measurement range
Accuracy, typically
Measuring time (s)
Statistical deviation (mm)
Resolution (mm)
Dimensions (L x W x H)
Weight
Protection class
Diameter of the infrared
measuring beam
2 m to 100 m
3 m to 7 m
-10 °C to +50 °C
2 m to 10 m
-20 °C to +60 °C
±15
0.1
5
±10
0.2
5
±7
0.5
2
±5±20
10.05
210
approx. 1.5 kg
200 x 130 x 76 mm
IP64
approx. 30 mm at 10 m,
approx. 150 mm at 50 m
±15 mm
LD90-3100HS-HT high-temperature distance meter
Operation
Storage
Temperature range (case temperature)
liquid steel, temperature up to 1450 °C
glowing slabs, temperature up to 1200 °C
other targets, temperature up to 800 °C
depending on the surface temperature and the
reflection coefficient of the target
The LD90-3100HS-HT is a laser distance meter optimized for very hot and glowing targets in steel plants, rolling mills,
foundries etc. Transmitter and receiver optics are equipped with narrow-band optical filters to avoid disturbances of
the measurement caused by the radiation of light and heat from the hot target surface. If necessary the front side can
be equipped with an additional protection tube, which can be flushed with nitrogen or compressed air to keep the
lenses clean.
The can, to a considerable extent, be influenced by the environmental conditions, especially by the
following parameters:
technical data
Surface temperature and reflection characteristics of the target
Distance of the target
Angle of the measurement beam with respect to the surface of the target
Optical attenuation of the gases between target and instrument
1)
2)
3)
3)4)
selectable via RS232/RS422
depending on measuring time
1)
4)
2)
3)
choosen automatically by the internal microprocessor
standard deviation
Eye safety class according to
IEC60825-1:1993+A1:1997+A2:2001
The following clause applies for instruments delivered into the United States:
Complies with 21 CFR 1040.10 and 1040.11 except for deviations
pursuant to Laser Notice No. 50, dated July 26, 2001.
laser class 3R
- 9 -

9pole socket for RS232/RS422
(1)
(2) LED "POWER ON"
(3) 10pole socket for power supply,
(4) Fuse holder
optional analog outputs,
data interface
Mounting plates with 2xM6 threads(6)
(5) Rubber-armoured front and rear panel
on both sides of the instrument
(7b) Telescope (optional)
(7a) Mounting for aiming device (optional)
Protecting filter for receiver lens (detachable)(8)
(9) Protecting filter for transmitter lens (detachable)
118
70 30
85
30
5
7a
6
5
7b
200
Information contained herein is believed to be accurate and reliable. However, no responsibility is assumed by
for its use. Technical data are subject to change without notice. RIEGL
Data sheet LD90-3100HS-HT, 08/06/2006
130
1
4
3
276
Power suppl y:
Dataoutput:
Meas. range:
RS232/RS422
11-28 V D C
Type: LD90-3100HS-HT
RIEGLLaser MeasurementS
y
stemsGmbH
A-3580 Horn AUSTRIA
8
9
Dimensional drawings of LD90-3100HS-HTRIEGL
Other parameters as given in our general data sheet LD90-3 series.
and switching output
, A-3580 Horn, Austria
Tel.: [phone], Fax: [phone], E-mail: off[email protected]
RIEGL Laser Measurement Systems GmbH
RIEGL USA Inc.
, Orlando, Florida 32819, USA
Tel.: [phone], Fax: [phone], E-mail: [email protected]
RIEGL Japan Ltd. , Tokyo 1640013, Japan
Tel.: [phone], Fax: [phone], E-mail: [e-mail]
www.riegl.com
- 10 -

2 Safety and Reliability
Contents:
∗General Safety
EN61010 (3 pages)
∗Electromagnetic Compatibility
EN61326 (2 pages)
∗Laser Safety
IEC60825-1:2001 (5 pages)
- 11 -

GENERAL SAFETY EN 61010-1
LD90-3 meets or exceeds the requirements of the following European
Standard: EN 61010-1:2001 Safety requirements for electrical equipment for
measurement, control, and laboratory use Part 1: General Requirements
Note the following explanations and important instructions:
Temperature: The unit is specified for a temperature range of -10 °C to
+50 °C (operation) and -20 °C to +60 °C (no operation).
Therefore, it is especially important that:
The housing temperature should always lie between -10°C
and +50 °C when the instrument is switched on.
Sunlight: The LD90-3 makes use of the optical time-of-flight technique
to determine the distance to the object in question. For this
purpose it comprises sensitive optical, electric and
mechanical components. Thus the LD90-3 requires
appropriate handling:
Direct sunlight or a similarly intensely radiating source of
light in axial direction of the lenses (in other words, in the
direction of the longitudinal axis of the instrument) must be
avoided. It is also important to avoid direct sunlight when
mounting or dismounting the instrument. Looking directly at
the sun or its immediate surroundings is not permitted
with the LD90-3, because of the danger to the eyes (when
the optional telescope is used) and to the sensitive
electrooptic components!
Altitude: The unit is specified for an altitude up to 2000m (operation).
Relative
Humidity: The unit is specified for a relative humidity of 80% at or belo
w
+31°C; linearly decreasing to 50% at +40°C.
Enclosure: The instrument LD90-3 is water resistant on the outside but
must not however be subjected to rain or dripping water o
r
submerged under water. Moreover it has to be protected
against chemical influences.
The rubber fittings can be cleaned from time to time with a
cleaning product specially intended for rubber (e.g. Sonax
plastic and rubber cleaner).
The lenses should be treated with the care customarily due to
optical instruments and, only when absolutely necessary,
should they be gently cleaned using a suitable lens cleaning
fluid (e.g. pure ethylene alcohol).
- 12 -

GENERAL SAFETY EN 61010-1
Never apply mechanical force or shock to the lenses or
to the housing itself!
As with other optical instruments, the LD90-3 should be
protected from being shaken or knocked.
Mounting: For fulfilling the high dynamic demands according to EN
61010-1 (sub-clause 8.3) the instrument has to be shoc
k
proof mounted. The lenses as well as the rear panel
assembly do not provide any harm in case of being
damaged. Therefore, they were excepted for the tests o
f
strength and shock described in EN 61010-1 (sub-clause 8.1
and 8.2).
If the instrument is mounted on both sides, please note that it
must not be twisted or constricted in any way.
When mounting the instrument do not under any circum-
stances use force. Never use rough tools e.g. a hammer o
r
chisel even if the fitting is not good.
In case of doubt, the after sale service centre of the
manufacturer will be pleased to advise, free of charge, on
how to best mount the instrument.
Power Supply: Before operating the LD90-3, make sure that its case is
properly grounded.
The DC-power supply has to fulfil the requirements fo
r
'Limited Circuit' according to EN 61010-1 and the
requirements for 'SELV' circuits according to EN 60950.
The power supply cable is to be connected with a suitable
DC-power supply with a maximum voltage of 28 VDC. The
negative pole of the supply voltage has to be grounded.
The positive pole of the DC power supply has to be
protected, also by a fuse 1 A time lag (T 1 A, according to
EN 60127 and IEC 60127), in order to avoid an excessive
current over the GND input wire in case of a false polarit
y
connection of the distance meter with the power supply.
The current drain capacity of the power supply must be at
least three times the rated current of the fuse, so the fuse
can be activated reliably if necessary.
The negative power supply input pole is directly connected to
the instrument’s housing. This should be remembered when
connecting it to other instruments..
The instrument must never be connected to
110, 230, or 400 V AC! Opening the instrument is
unacceptable due to the danger presented by the high
voltages, and must therefore be avoided at all costs.
- 13 -

GENERAL SAFETY EN 61010-1
Data and
Control Inputs
and Outputs:
The control inputs and the serial interface of the laser dis-
tance meter may be connected only to equipment fulfilling the
requirements for 'SELV' circuits according to EN 60950.
ANY USE OF THE LD90-3 IN CONTRADICTION TO THE
INSTRUCTIONS AS GIVEN IN THE HANDBOOK CAN BE DANGEROUS
AND IS, THEREFORE, STRICTLY FORBIDDEN!
- 14 -