Velemeter® Series 500


Additionally to the well established Velemeter 500 series a new compact sensor is available. This model is called Velemeter C - it is designed for use in or attached to C-frames of thickness gauges. It has already an integrated angle optic.

Nowadays, it is possible to control the mill gauge in a way that variations in the thickness of the material at the entry side are eliminated in the mill by using the material speed and the measured thickness for mass flow control. However, the new drive technology and the possibilities of gauge control are also responsible for the need of new techniques for speed measurement. The old existing mechanical detectors are no longer state-of-the-art.

The main applications for mass flow control are in the aluminium and stainless steel industry. For the speed measuring device itself, it makes no difference. In all applications VELEMETER® 500 is used.

The gauge head is typically integrated in the extractor hood at the entry and exit side where also the thickness gauges are installed. In some applications, the gauge head is equipped with an angle optic, so that it is possible to mount the gauge head at the same c-frame as the thickness gauge.

Since nearly all new rolling mills nowadays have built-in lasers, the users of old mills know that it is absolutely essential to re-equip their old mills with new measuring and control technology.

For cooling purposes the gauge head is equipped with a liquid-cooled housing which can be supplied from existing cooling facilities or with an own temperature control device or chiller. The VELEMETER® 500 is also able to use the emulsion which is used at the mill for cooling. It is also essential that the laser is able to see the material under all rolling conditions. Therefore, an air purging device which is directly mounted at the laser gauge is used.

As the mass flow control itself is typically supplied by the contractors for the electri-cal part of the mill, it is necessary to con-nect the VELEMETER Model 500 to a host computer. For this reason, the system has a standard pulse output with a resolution of 10 µm.


Technical details


Speed measuring range:

Modell A: 12 - 3.000 m/min - 0,2 - 50 m/s
Modell B: 0 - ± 3.000 m/min - 0 - ± 50 m/s

Length measuring range: unlimited
Input / output : standard: pulses status and parameter via RS 485
option: all industrial interfaces via PC
Value of length pulses: Model A
~10 µm pulses, no quadrature signal
~40 µm * n (n = 1 - 255) quadrature pulses 
Model B
~10 µm quadrature pulses
~40 µm * n (n = 1 - 255) quadrature pulses
Voltage of pulses: 5 V
supply by the user between 5 and 24 V
Accuracy: +/- 0.05%
Repeatability: +/- 0.01%
Resolution: ca. 10 µm
Stand-off distance: 1000 mm standard,
optional 500 – 2000 mm
Depth of field: +/- 50 mm at 1000 mm stand-off
Laser light source: 5 mW He/Ne- Laser tube
632.8nm, red, visible
Lifetime of laser: minimum 5 years
Power supply: 110/240 V, 50/60 Hz
Ambient temperature range: Sensor: 0 – 40º C without cooling
PKE: 5 – 40º C
Cooling for sensor if t > 40°: C 3 l/min, liquid at max. 30º C
pH neutral
no particles > 100 µm
pressure max. 6 bar
IP rating: Sensor IP 67
Air quality for air wipe: Dried plant air 10 m³/h,
free of water and oil
no particles > 8µm
Air quality in the beam path: clean - free of dust, steam or water


* depends on the stand-off