LaserSpeed Pro – Metals

LaserSpeed Pro LS8500, LS9500 non contact speed & length measurement


The LaserSpeed Pro LS8500 & LS9500 are our most advanced models and are suited for all application including for use in the tough environment found in the metals industry. They use advanced laser-based technology to perform length and speed measurements without contact. It will measure with a high accuracy of better than  ±0.03% and repeatability of ±0.02% on any material irrespective of the surface properties. The laser Doppler principle measures surface speed and provide a very fast update rate of only 1 ms. Regardless of your productions line speeds or product type LaserSpeed delivers precise repeatable measurements day-in, day-out. Unlike contact encoder wheels the LaserSpeed is not susceptible to errors due to slipping, wheel pick up or wear and will provide a more dependable measurement over the long term. They are suitable for use on any production line including the harsh environments found in hot and cold steel and aluminium rolling mills.

LaserSpeed Applications

Elongation/differential speed measurement Coil length or speed measurement Cut-to-length control
Hot section saw control Tube length measurement Continuous caster speed & length measurement
Billet or section length measurement Process speed or stretch levelling Forward/reverse positioning applications

Operating Principle

All LaserSpeed sensors use the principle of dual-beam laser Doppler velocimetry to produce highly accurate measurement without contacting the product. The gauge has no moving part, uses 100% solid state digital technology and is permanently calibrated.


  • Speed measurement of continuous casters
  • Elongation ratio in cold strip mills
  • Final slab or billet length measurement and verification
  • Mass flow AGC applications
  • Torch cutter control on continuous casters
  • Elongation on stretch levelling machines
  • Measurement of length of tubes
  • Coil length measurement
  • Measurement of hot or cold bars
  • Shear control
  • Speed or length on process / inspection lines
  • Cut-to-length control

LaserSpeed® pedigree

LaserSpeed gauges can measure the speed and length of any products using an optical, non-contact technology called Dual Beam Laser Doppler Velocimetry. LaserSpeed gauges were first introduced to the metals industry in 1984 and have been growing in usage ever since. There are now thousands of LaserSpeed gauges installed worldwide There is a wide range of models to suit every application whether measuring hot or cold materials.

High performance

A breakthrough in electro-optics design enables LaserSpeed gauges to produce highly accurate, non-contact speed and length measurements at a reasonable cost. To accomplish this the LaserSpeed gauge uses Laser Doppler Velocimeter technology coupled with autocorrelation, the most advanced, digital signal processing algorithm and a new single-chip integrated circuit technology. LaserSpeed gauges have no moving parts, use 100 % solid-state digital technology, and are permanently calibrated – resulting in significant time and money savings.

Replace contact tachometers

With an accuracy better than ±0.03%, irrespective of the material, temperature, surface or speed the LaserSpeed is ideal for replacing traditional contact tachometers that are prone to measurement errors caused by slippage, dirt build-up, and day-to-day wear problems.

Measure zero speed and direction

The LaserSpeed LS9500 models use an enhanced version of autocorrelation, coupled with an Acusto-Optical modulator that enables the gauges to measure down to zero speed and automatic direction detection. These gauges are ideal for measuring the length of material on start/stop processes such as sawing lines. The gauge can even track forward or reverse movement without affecting the length accuracy.

Suitable for harsh environments

All LaserSpeed gauges are extremely rugged with a sealed IP67 housing with built-in air/water cooling facility. For use within a mill environment with extremes of heat, steam and spray additional levels of protection are provided by the E or X versions of the gauge.

LaserSpeed Pro LS8500 & LS9500

Features Benefits
Non-contact measurement Materials that are impossible or difficult to measure with traditional contact methods due to slip or wear can now be measured accurately
No maintenance There is no wear compared with contact roll measuring systems, significantly reducing running costs and on-going maintenance
High accuracy Measuring to better than ±0.03% means better process control and saving in material and better quality
Rugged construction Suitable for use in any mill environment
explication Permanent calibration Reduces running costs as frequent recalibration is not required
Intelligent sensor All electronics built in no need for separate processor
LaserTrak software Supplied with simple Windows software to configure the sensor
Options & accessories Large range of accessories means that the sensors are suitable for most applications straight out of the box

LaserSpeed Pro LS8500 & LS9500 model versions

LS8500  LS9500 The base sensor for all the models in the LaserSpeed series of gauges. Accuracy is better than ± 0.05%, with built-in electronics. The LS9500 model can measure zero speed and determine the direction the material is moving. LaserSpeed LS8000/9000 model
LS8500E  LS9500E The base sensor housed in a second rugged housing for double sealed protection against hot and hostile environments. The LS9500E model can measure zero speed and determine the direction the material is moving. LaserSpeed LS800E/9000E model
LS8500X  LS9500X This version offers the ultimate protection where heavy steam, mist and spray occurs. Housed in stainless steel air-purged housing. Suitable for use directly in the mill. LaserSpeed LS8000X/9000X model
LS8500C This version is designed to mount directly inside a C-frame of an X-ray thickness gauge. Adjustable mount means that the stand off can be optimised to suit the application. LaserSpeed LS8000-C model

LaserSpeed Pro LS8000 & 9000 specification

Model Stand off
Depth of
field (mm)
range (m/min) (LS9500)
LS8500-403 / LS9500-403 300 35 0.4…40000 / (0…±4000)
LS8500-406 / LS9500-406 600 50 0.8…80000 / (0… ±8000)
LS8500-410 / LS9500-410 1000 100 1.0…120000 / (0… ±12000)
LS8500-415 / LS9500-415 1500 200 2.0…190000 / (0… ±19000)
LS8500-420/ LS9500-420 2000 200 3.0…200000 / (0… ±20000)
LS8500-425 / LS9500-425 2500 200 4.0-200000 / (0… ±20000)
Accuracy DoF < 100 mm (DoF > 100 mm) <±0.03% of reading (<±0.07% of reading)
Repeatability ±0.02%
Measuring rate LS8500 (LS9500) >50,000/sec (>100,000/sec)
Acceleration rate >500 m/s²
Measuring rate 1-64 ms user programmable
Serial I/O RS232 & RS422, speed, length, quality factor, status
Quadrature pulse output 1 Selectable pulse rate up to 250 kHz
Quadrature pulse output 2 RS-422 drivers, Selectable pulse rate up to 5 MHz
Analogue output 0-2V velocity or QF
Ethernet (optional) 10/100 UDP, TCP, speed, length, Quality factor, status
Fieldbus Ethernet (Modbus TCP, Ethernet IP, Profinet IO); Profibus DP
Gauge power LS8000 (LS9000) 24VDC (±4) @ 1.5 Amp (24VDC (±4) @ 2.0 Amp)
Gauge temperature 5 to 45 °C
Gauge size (-403, -406) 203 x 159 x 97.5 mm
Gauge size (-415, -420, -425, 430 models) 229 x 159 x 97.5 mm
Degree of protection (all models) IP67