- The VLM502 works optically and contact-free. Based on a CCD sensor it implements the spatial filter principle. Spatial filter is the generic term for a measuring principle for the optical determination of velocity and length of moving objects.
- The spatial filter is based on the filtering effect of lattice-like structures (grid modulation). Basically, the functional principle of the VLM502 can be described as follows: The illuminated measuring object is projected through lenses on the CCD sensor which acts as an optical grid. The VLM502 is equipped with a LED light source for the illumination. Due to the grid modulation a signal frequency, which is proportional to the speed, occurs upon movement of the object. The device calculates the velocity from the measured signal frequency. Several control circuits loops for an automatic adjustment to most diverse materials.
- There are rarely requirements on the surface character of the measuring object. Precise measurements are facilitated on periodic structures as well as on stochastic surfaces of metals, wood, rubber or paper.
Thông số kỹ thuật
- Nominal distance : 85 mm
- Working range : max. ±15 mm
- Measuring range : 0.6 ... 3000 m/min
- Measuring uncertainty : < 0.025 % in nominal distance
- Reproducibility : < 0.025 %
- Averaging-/Update-Time : > 0.2 ms with additional 1 ... 32 times sliding average
- Length measuring range : Internal length range up to 2,000,000 km
- Detector / principle : CCD sensor / spatial filter with semiconductor grid as reference
- Illumination : White light LED (expected life span: > 5 years 2))
- State indicator (VLM502 - E) : Sginal (green), Error signal (red), Communication (yellow), Forward (Green), Backward (green)
- Power supply, consumption : 24 VDC max. 25 W
- Temperature range : 0 °C ... 50 °C
- Protection class : IP 65
- EMC : Industrial standard in compliance with CE
- Weight, Housing dimensions : VLM502 - O: approx. 1,7 kg, 135 mm x 140 mm x 67 mm (without connections) ; VLM502 - E: approx. 2,2 kg, 140 mm x 140 mm x 91 mm (without connections)
- Programming interface (max. 2) : for parameter setting, data output and firmware update: USB (IUSB), RS-232 (I232), RS-422/RS-485 (I4UN), isolated
- Opto-isolated outputs : 2x (Error, Signal status)
- Opto-isolated inputs : 3x (External trigger signal, Idle mode / Lock, Definition of the direction of the movement
- Pulse output (Encoder) : A/B, 2 phases 90°, Resolution 8 ns, 0.2 Hz ... 25 kHz ; Optionally as Open Collector (IPPL), 5V TTL (IP5V) or Push Pull (IPPP)
- Analog output : Current output, adjustable as 0 ... 20 mA, 0 ... 24mA, 4 ... 20 mA (IAUN)
- Fieldbus interface : Profibus DP (IFBP), Telnet via FastEthernet (IFFE), Profinet IO (IFPN)
- Standard scope of delivery : VLM500, Programming interface on customer request, Power supply cable, Connection cable, connection cable between gauge head and evaluation unitpositioning aid, USB memory stick with documentation and software, printed manual