LMI Selcom SLS 5000 User manual

User’s Manual
SLS 5000
SLS 6000
SLS 2401
SLS 2008

LMITechnologies
PROPRIETARY
This document, submitted in confidence, contains proprietary information which
shall not be reproduced or transferred to other documents or disclosed to others or
used for manufacturing or any other purpose without prior written permission of
LMI Technologies Inc.
http://www.sensorsthatsee.com
Trademarks and Restrictions
Selcom is a registered trademark of LMI Technologies Inc.
This product is designated for use solely as a component and as such it does not
comply with the standards relating to laser products specified in U.S. FDA CFR
Title 21 Part 1040.
No part of this publication may be copied, photocopied, reproduced, transmitted,
transcribed, or reduced to any electronic medium or machine readable form
without prior written consent of LMI Technologies Inc.
Printed in The Netherlands.
Information in this document is subject to change without notice.
Copyright (c) 2006 LMI Technologies Inc. All rights reserved.
Printed in The Netherlands.

03-09-05 1
Table of contents
1INTRODUCTION 3
2TECHNICAL DESCRIPTION 4
Identification of parts 4
SLS5000 4
SLS 6000 4
SLS 2401 5
SLS 2008 5
Manufacturers serial number label 6
Measurement principle and definitions 7
Sampling frequency and bandwidth. 8
The analog position sensitive detector 8
Linearization 9
3TECHNICAL DATA 9
Block diagram 9
Dimensions 10
Environmental conditions 10
Power requirements 10
Performance 10
Sensor configuration 11
SLS5000 11
SLS6000 11
SLS2401 12
SLS2008 12
Analog Output 12
Digital Outputs 13
RS232-C 13
Selcom serial synchronous interface 13
RS422 14
Invalid output 14
4SAFETY REQUIREMENT 15
Symbols 15
Safety precautions 15
Summary of user precautions regarding laser 16
Emission delay 16
Safety of Laser products. 17
Maximum Permissible Exposures (MPEs) 17
Laser product classification. 17
Calculation of MPE and NOHD 18
MPE 18
NOHD 18
Warning labels 19
Laser Safety References 20

03-09-05 2
5INSTALLATION 21
Cable requirements 21
Analog output 22
Scale factor current output and engineering units 22
Load conditions for analog output. 25
Alternative connections for valid output 25
Cable crosstalk. 26
Electrical installations, examples 27
Mechanical installation. 29
For a single SLS sensor system 30
For a dual SLS sensor system 30
Hints for measurements 32
Material 33
Unstable thickness reading 35
Surface texture. Static texture error 35
Temperature of the material 37
Geometry of the material. Secondary reflections 37
6SERVICE AND MAINTENANCE 38
Keeping the front glass clean 38
Visual check for damage 38
LED-indicators (Yellow and Green) 39
7APPENDIXES 40
Appendix A, Revision page 40
Appendix B, Accessories 40
Appendix C, SLS-asynch-1, protocol 40
Appendix D, SLS power unit 24 51
Appendix E, Connection table 53
Appendix F, Quality Record 54
Appendix G, Dimensional drawings 57
LMI Technologies AB
Ögärdesvägen 19 A
Box 250,
S-43325 Partille
SWEDEN
Tel: [phone]
Main [phone]
Fax: [phone]
Internet: http://www.lmint.com
LMI Technologies (USA), Inc.
21455 Melrose Ave. Suite 22
SOUTHFIELD MI 48075
USA
Tel: [phone]
Fax: [phone]
LMI Technologies BV
Valkenburgweg 223
6419 AT Heerlen
The Netherlands
Tel: [phone]
Fax: ++31 45 574 2500
LMI Technologies Inc.
205-7088 Ventura Street
Delta, BC, V4G-1H5
Canada
Tel: [phone]
Fax: [phone]
Printed in The Netherlands

03-09-05 3
1 INTRODUCTION
This manual is a description of the Selcom Laser Sensor (SLS) family. The
sensors have laser classification 2, 3R or 3B. Read chapter Laser Safety
precautions before connecting the sensor.
This sensor is intended for use in applications where distance, thickness or level is
to be measured. The ambient temperature surrounding the sensor should be 0°C to
50°C but the temperature of the measured object may vary from deep frozen to
+1600°C. The sensor is equipped with a temperature guard that shuts the laser off
should the surrounding temperature exceed the limits.
No changes or modifications may be made to the sensor or its cable unless you
have a written permission from LMI Technologies. If the sensor is opened or
modified without permission, warranty is voided.
Caution- Use of controls or adjustments or performance of
procedures other than those specified herein may result in
hazardous radiation exposure.
For your own safety, follow the instructions in this manual.
If you get problems when using the SLS sensor, contact your local LMI
Technologies office or your local distributor.
The delivery of a SLS 5000 contains:
• SLS 5000 sensor
• Isolation washers 8 pcs
• Users manual 1 pcs
The delivery of a SLS 6000 contains:
• SLS 6000 sensor
• Isolation washers 4 pcs
• Users manual 1 pcs
The delivery of a SLS 2401 contains:
• SLS 2401 sensor head and SLS Controller
• Isolation washers 4 pcs
• Users manual 1 pcs
The delivery of a SLS 2008 contains:
• SLS 2008 sensor head and SLS Controller
• Isolation washers
• Users manual 1 pcs

03-09-05 4
2 TECHNICAL DESCRIPTION
Identification of parts
SLS5000
Figure 1: Identification of parts SLS 5000
SLS 6000
Selcom
LASER MEASUREMENTS
SLS 6000
DANGER
Laser
Class 3B
Laser emitting
label
Air purge inlet Mounting Holes
M8 (4X), top mount
Receiver ApertureLaser aperture, incl laser shutter
Manufactures serial
number label
Emission indicator:
1.Illuminated when power is on
2. GREEN when target is within
the measurement range.
3. YELLOW when no target is present
within the measurement range.
Figure 2:SLS 6000
Mounting holes
SELCOM
SLS5000
Laser emitting
lable
Laser aperture Receiver aperture
Emission indicator device
1, Illuminated when power is ON
2, Green when target is within the
measurment range
3, Yellow when no target is present
within the measurment range
Front glass
Side vie
w
Front view
Laser shutte
r
Manufacturers serial
number label

03-09-05 5
SLS 2401
Emission indicator on 2401 head is RED when laser is ON. Function of Emission
Indicator on SLS controller see previous page
Figure 3. SLS 2401. SLS controller top and 2401 head bottom.
SLS 2008
Emission indicator on SLS2008 sensor head is RED when laser is ON.
Figure 4. SLS controller

03-09-05 6
Figure 5. SLS2008 sensor head
Manufacturers serial number label
Selcom
BOX 250 S-433 25 PARTILLE SWEDEN
810555 SLS2070/200-WO
345 0-20 mA
NOVEMBER 1996
PART NO TYPE
SN OUTPUT
MANUFACTURED:
MONTH YEAR
1
2
4
6
3
5
7
8
Figure 3: Manufacturers serial number label
The serial number label contains the following information:
1. The address of the production location.
2. The part number of the product. Refer to this part number when contacting
LMI Technologies.
3. Type description of the sensor. SLS5070/200-BM means:
SLS5000
Measurement Range = 70 mm
Stand Off = 200 mm
Optimized for Building Material (BM) applications
Other applications are:
MM = Molten metal
RO = Road
RU = Rubber
SW = Saw mill

03-09-05 7
Other letter combinations may occur.
4 Serial number of the sensor. Refer to this serial number when contacting LMI
Technologies.
5 Available outputs, one analog and one digital. The outputs are selected when
ordering the sensor. Possible combinations are:
0-20 mA / Selcom or 4-20 mA / Selcom
0-20 mA / RS422 or 4-20 mA / RS422
RS232 is always available, ref to appendix for details.
6 Month of manufacture.
7 Year of manufacturer
8 CE-mark. Indicates that the product fulfills the emc-directive according to EN
89/336/EEC
Measurement principle and definitions
The SLS sensors consist of a light source and a detector integrated with optics and
electronics. The light source is a semi conductor laser diode operating in a pulsed
mode with 50% duty cycle. The pulse rate or frequency is 16 000 times per
second.
This laser diode illuminates a spot on the surface of the object to be measured,
(log, car body, gypsum board etc.).
The spot is not only detectable to the human eye but also clearly visible to the
detector of the SLS. The detector is situated at the back of the receiver part,
similar to the retina of the human eye.
Stand Off
Distance, SO
Measurement Range, MR
Semiconductor
laser and optics
Receiver optics
PSD
(Position Sensitive photo Detector)
Close End, CE
Far End, FE
Figure 4: Measurement principle and definitions
Depending of the distance between the SLS sensor and the light spot, the Stand
Off distance, the image of the light spot will be focused on a certain spot on the
detector. The detector is a high resolution, position sensitive detector. It converts
the light spot to electrical signals from which the electronics can calculate the
actual distance to the object.
”Moving objects, no problem”
The measurement is very rapid. The SLS sensor repeats the measurement
sequence 16000 times per second. This makes it possible to measure moving and
vibrating objects.
By using several SLS sensors you can measure thickness, profiles, diameter, etc.

03-09-05 8
The accuracy is high; the error is normally less than 0.2% of the measurement
range.
Sampling frequency and bandwidth.
Sampling frequency and bandwidth are related but not identical quantities. The
sampling frequency tells how often the sensor evaluates the raw analog signal by
performing an A/D conversion. The bandwidth value tells how that analog signal
is conditioned before the A/D conversion. In order to avoid certain signal
processing problems, the bandwidth has to be lower than the sampling frequency
(it may not exceed 50% of the sampling frequency), and for that reason the signal
is put through an analog filter stage before the A/D conversion. Although it is not
a theoretically correct way to express it, one might say that the bandwidth
determines how fast a measurement signal may change, and have the change
detected by the sensor.
The analog position sensitive detector
12
Incoming light
X
Light spot
I1 I2
0
Typical size of the detector is 1*10 mm
Figure 5: The analog position sensitive detector
The detector current, generated by the light spot is divided into two parts: I1 and
I2.
The distances between the light spot and the electrodes 1 and 2 give the ratio
between the currents.
2.1.1.1 Advantages
Advantages:
1 Fast. Rise time 10-90 % (typical) = 0.2 µsec.
2 High suppression of ambient light.
3 Very high resolution. Limited only by the following Analogue-to-Digital
converter.
The technique also enables fast regulation of the output laser power. This fast
regulation makes measurement of almost any material or surface possible and
allows for fast and big variations of measured surfaces color and reflectiveness.

03-09-05 9
Linearization
SELCOM
SLS5000
Scattered
light reflection
A small portion of
the scattered light
Detector output
Desired
function
Non-linearized
function
The function between the raw output from the detector and the actual distance
between the SLS sensor and the measured object is non-linear. This non-linearity
is mainly due to the geometry of this type of measurements and to the analog
portion of the data processing. Therefore each sensor is factory calibrated to
compensate for any non-linearity or other built-in error. Using a moving target
and a reference scale a translation table is constructed and stored in non-volatile
memory inside the sensor.
Figure 6: Illustration of linearization
3 Technical data
Block diagram
Principal diagram:
DSPPreamplifierx1
x2
A/D-conv.
x1+x2
x1-x2
Laser
driver
Control
logic
Host processor
Internal data bus
Interface
Power
regulator
+ 24 VDC
Laser
diode PSD
Figure 7: Principal diagram

03-09-05 10
Dimensions
SLS5000
Length: 135 mm (5.3 inches)
Height: 105 mm (4.1 inches)
Width: 51 mm (2.0 inches)
Weight: 1.1 kg (2.2 lbs)
SLS6000
Length: 376 mm (14.8 inches)
Height: 169 mm (6.6 inches)
Width: 70 mm (2.7 inches)
Weight: 4.4 kg (9.9 lbs)
Environmental conditions
Temperature:
Operating: 0-50 °C (32-120 °F)
Storage: -30-70 °C (-20-160 °F)
Protection class :IP65 (NEMA 4)
(Excluding connector)
Power requirements
Input voltage :+24 VDC (18-32 VDC)
Input current: 250 mA at 24 V (350-200 mA for 18 -32 V)
Start-up current: typical 1,1 A for 8 ms
Performance
Resolution
0.025 % of Measurement Range
Inaccuracy
0.2 % of Measurement Range (Includes non-linearity and error)
Sampling rate
16 kHz
Bandwidth
Up to 2 kHz depending on configuration settings

03-09-05 11
Sensor configuration
Measurement Range (MR), Stand Off (SO), Beam divergence angle
SLS5000
MR (m m) SO (m m) Spot size at
SO (mm)
Beam
divergence (rad)
Resolu tion
1 LSB= (um)
6 50 0,1 0,060 1,50
20 50 0,1 0,060 5,00
10 100 0,1 0,030 2,50
20 100 0,1 0,030 5,00
35 100 0,1 0,030 8,75
35 200 0,3 0,025 8,75
70 200 0,3 0,025 17,50
100 200 0,3 0,025 25,00
70 300 0,3 0,017 17,50
150 300 0,3 0,017 37,50
200 300 0,3 0,017 50,00
325 400 0,5 0,013 81,25
400 450 0,6 0,011 100,00
750 600 0,8 0,008 187,50
1000 1250 1,0 0,004 250,00
SLS6000
MR (m m) SO (m m) Spot size at
SO (mm)
Beam
divergence (rad)
Resolu tion
1 LSB= (um)
50 400 0,5 0,013 12,50
362 480 0,6 0,010 90,50
100 500 0,6 0,010 25,00
175 500 0,6 0,010 43,75
250 500 0,6 0,010 62,50
362 500 0,6 0,010 90,50
510 600 0,7 0,008 127,50
180 738 0,7 0,007 45,00
225 750 0,7 0,007 56,25
375 750 0,7 0,007 93,75
525 750 0,8 0,007 131,25
375 1000 1,0 0,005 93,75
575 1000 1,0 0,005 143,75
725 1000 1,0 0,005 181,25
300 1250 1,2 0,004 75,00
550 1250 1,2 0,004 137,50
850 1250 1,2 0,004 212,50
1000 1250 1,2 0,004 250,00

03-09-05 12
SLS2401
MR (m m) SO (m m) Spot size at
SO (mm)
Beam
divergence (rad)
Resolu tion
1 LSB= (um)
20 50 0,06 0,060 5,00
50 80 0,09 0,038 12,50
SLS2008
MR (mm) SO (mm) Spot size at
SO (mm)
Beam
divergence
(rad)
Resolution
1 LSB=
(um)
325 1350 2,0 0,004 81,25
325 1600 2,0 0,003 81,25
325 1800 2,0 0,003 81,25
325 2010 2,0 0,002 81,25
Analog Output
Output signal interface: Analog
current source
external impedance: max 500 Ω
max cable length: 100 m
selectable at delivery
(see manufacturers
serial number label):
0-20 mA
Far end value: 0 mA
Close end value: 20 mA
Resolution: 4.88 microA/LSB
or 4-20 mA
Far end value: 4 mA
Close end value: 20 mA
Resolution: 3.90 microA/LSB
time [ms]
Tc
Td
Step function
Analog output
Figure 8: The step response

03-09-05 13
Td = delay time, Tc = time constant
Time Error (% of step)
Tc 36 %
2Tc 13 %
3Tc 5 %
4 Tc 2 %
External impedance = 500 ΩTd = 200 µs.
Tc = 80 µs. (at 2 kHz bandwidth)
External impedance = 500 Ω+ filter according to appendix C.
Td = 300 µs.
Tc = 100 µs. (at 1.6 kHz bandwidth)
Digital Outputs
RS232-C
No hardware handshaking
Protocol: SLS-ASYNCH-1
Ref: Appendix
Optional
digital:
Selcom serial synchronous interface
The ”Selcom” output is a proprietary synchronous serial output. It uses a clock
and a data signal; with the clock only running while data is being transmitted.
Each data item is 16 bits . The same physical output can also be configured in for
serial as RS422. The Selcom serial is a gated clock /inverted clock and data and
data inverted according to the figure below. MSB is the most significant bit and C
is the “Invalid” bit.
11 10 987 6 5 4 3 2 1 0 C CC
Data
Data
Clock
Clock
LSB MSB
Figure: Selcom serial synchronous output. Clock rate 16 kHz, gated clock
Logical ”1”: C > 0.6 V + C-inv.
D > 0.6 V + D-inv.
Logical ”0”: C-inv. > 0.6 V + C
D-inv. > 0.6 V + D
Max. Load : (OH = Output High, OL = Output Low)
Voltage: U(OH) > 2.0 V
U(OL) < 0.8 V

03-09-05 14
Current: I(OH) > 40 mA
I(OL) < -40 mA
or
RS422
Full duplex
Protocol: SLS-ASYNCH-1
Ref: Appendix E
Invalid output
Inv.out +
Inv.out -
100 ohm
Figure 9: Optocoupled
Max ratings: VCE 35 V
IC50 mA
Rise time
(typical):
60 µs
Fall time
(typical):
53 µs

03-09-05 15
4 SAFETY REQUIREMENT
Symbols
The following symbol appears in the manual:
The symbol identifies conditions or practices that are hazardous
Safety precautions
The light source of the SLS is a semiconductor laser emitting visible or invisible
light. The SLS has a 2, 3R or 3B classification according to IEC 60825-1 Safety
of Laser products and complies also with FDA performance standards for
laser products except for deviations pursuant to Laser Notice No. 50, dated
July 26, 2001.
The classification for each sensor is stated on the laser warning labels on the
sensor. Make sure that you take the proper precautions for the laser class of the
sensor you are using. If you are uncertain of the laser class or if you have
questions regarding precautions or laser safety standards, please contact your
nearest LMI office. The following safety precautions must be observed when
working with the equipment:
The emitted light can damage the eye if directly exposed, or if the
laser light is reflected by a mirror or any mirror like surface
directly into the eye.
Follow all warnings and instructions in the manual. Personnel working with or
near the SLS must be informed about safety distance, hazardous area and other
installation specific hazards.
Caution- Use of controls or adjustments or performance of
procedures other than those specified herein may result in
hazardous radiation exposure.
Ensure that the voltage from the power supply matches the specifications for the
equipment.
If otherwise is not explicitly stated, always disconnect the power supply unit
during installation, service and maintenance of the SLS. The power supply unit
delivered from LMI Technologies is provided with a key control. Remove this
key to prevent that the laser is turned on unintentionally.
If possible seal off the hazardous area defined in the Safety distance/ NOHD
section to prevent unauthorized personnel from getting exposed to laser light.
It is always recommended to follow as many of the precautions as possible
irrespective of laser class.

03-09-05 16
Summary of user precautions regarding laser
For products with a laser safety class 2, 3R or 3B (See text of IEC 60825-1 for
complete precautions, subclause indicated in table):
Requirements
subclause
Class
3B 3R 2
Laser safety
Officer, 10.1
X
For 3R --required only if non visible radiation
Remote
interlock, 10.2
X
Connect to room or door circuits. Pin no 14 (LASER ON) of
the SLS connector can be used for this purpose.
Key control
10.3
X
Remove key when not in use.
Key control is provided when power supply is delivered by
LMI Technologies. To conform to safety requirements a key
control must be installed. Use pin no 15 (+24 VDC) of the
SLS connector to /connect/disconnect the power of the SLS.
Beam
attenuator
(Laser shutter)
10.4
X
When in use prevents inadvertent exposure.
Provided by LMI Technologies and permanently mounted
on the front of the sensor. See chapter 2, figure 1.
Emission
indicator device
X (X) Indicates that the laser is energized. Required for 3R only if
nonvisible laser.
See chapter 2, figure 1.
Provided by LMI Technologies and permanently mounted
on the side of the sensor. One of the LEDs is always lit.
• The yellow LED is lit when the sensor signals Invalid,
e.g. no object inside the measurement range, too little
light scattered back to the detector, to much light
scattered back to the detector.
• The green LED is lit when the measurement is Valid
Warning signs,
10.5
X
Follow precautions on warning signs.
Beam path,
10.6
X X Terminate beam at the end of its useful length.
Specular
reflection, 10.7
X X Prevent unintentional reflections
Eye protection,
10.8
X Required if engineering and administrative procedures not
practicable and MPE exceeded.
Protective
clothing, 10.9
X Not required
Training, 10.10 X X Required for all operator and maintenance personnel.
Emission delay
LMI Technology’s sensors can be equipped with two different types of emission
delay. One (called Laser ON delay) will always cause a short delay every time
the laser control signal is turned on, before the laser actually starts emitting laser
light. The other type (called Power ON delay) will only cause a delay when the
sensor is first powered up. All subsequent cycling of the laser control signal will
control the laser without any delays. See quality record.

03-09-05 17
Safety of Laser products.
Maximum Permissible Exposures (MPEs)
IEC 60825-1, Safety of laser products, relies on the concept of the MPEs. The
MPEs are derived primarily from animal and human data, but take into account of
human variability and laser parameters Clause 3.55 of IEC 60825-1 defines the
maximum permissible exposures as “The level of laser radiation to which, under
normal circumstances, persons may be exposed without suffering adverse effects.
The MPE levels represent the maximum level to which the eye or skin can be
exposed without consequential injury immediately after, or after a long time, and
are related to the wavelength of the radiation, the pulse duration or exposure time.
The tissue at risk and, for visible and near infrared radiation, the size of the retinal
image. For calculation of MPE see “Calculation of MPE and NOHD in this
manual.
Laser product classification.
The classification of a laser product is based on the radiation emitted during the
normal operation and any reasonable foreseeable fault condition for that product.
4.1.1.1 Class 2 laser products:
Class 2 laser products would not cause permanent damage to the eye under
reasonable foreseeable conditions of operation, provided that any exposure can be
terminated by the blink reflex (assumed to take 0,25 s). Because classification
assumes the blink reflex, the wavelength must be in the visible range (400 nm to
700 nm). The Maximum Permissible Exposure (MPE) for visible radiation for
0,25 s is 25 W per square meter, which is equivalent to 1 mW entering an aperture
of 7 mm diameter (the assumed size of the pupil).
4.1.1.2 Class 3R laser products
Class 3R laser products emits radiation where direct intrabeam viewing is
potentially hazardous but the risk is lower than for Class 3B lasers, and fewer
manufacturing requirements and control measures for users apply than for Class
3B lasers.
4.1.1.3 Class 3B laser products
Class 3B laser products are unsafe for eye exposure. Usually only ocular
protection would be required. Diffuse reflections are safe if viewed for less than
10 s.
4.1.1.4 Nominal Ocular Hazard Distance (NOHD) or safety distance.
The NOHD is related to the Maximum Permissible Exposure (MPE). The NOHD
is the nominal distance at which the exposure equals the MPE. The concept of
NOHD is used when laser products such as range finders or display lasers are to
be used in the open air.

03-09-05 18
Stand Off
SO
NOHD
Aperture
SLS Laser
Exposure exceeds MPE Exposure does
Not exceed MPE
Beam divergence
Irradiance or Radiant Exposure equals M PE
Stand Off
SO
NOHD
Aperture
SLS Laser
Exposure exceeds MPE Exposure does
Not exceed MPE
Beam divergence
Irradiance or Radiant Exposure equals M PE
The NOHD is depending on Stand Off and working power and can be found in
the Quality record that comes with each sensor delivered. See appendix G-
Quality Record for the actual NOHDof your sensor and actual parameters for
your SLS in order to calculate MPE and NOHD.
Figure 10: The concept of nominal ocular hazard distance
Calculation of MPE and NOHD
MPE
See section 13 in the IEC80825-1. Parameters necessary to be able to calculate the
MPE are exposure time base, max pulse power, wavelength, pulse repetition
frequency and pulse duration. These parameters can be found as follows.
Parameter
Exposure time base Time base for MPE is 10 s for invisible
(see example A.4-2 in the IEC 60825-1 ed.
1.2) and for Visible 0,25 s (example A.4-
1).
Max pulse power, wavelength and pulse
duration
Explanatory label affixed to the product
Pulse repetition frequency Same as the term “Sampling frequency”
found in the Q-record.
16000 Hz for all SLS
4.1.1.5 MPE values for SLS.
The MPE values as well as the results of the calculation of each of three
requirements of 13.3 in IEC 80625 are stated in the table.
Wavelength 13.3 a
J/m2
13.3.b
J/m2
13.3.c
J/m2
Most
restrictive
J/m2
Most
restrictive
corresponds
to MPE
W/m2
655 nm (visible) 7,52E-03 1,59E-03 9,46E-04 9,46E-04 30,3
780 nm (NIR) 1,09E-02 9,14E-04 5,44E-04 5,44E-04 17,4
NOHD
See Annex A, section A.5 in the IEC standard and TR 60825-10. Parameters