Product Highlights

  • Mounting options -170, 185 & 240 mms
  • Pulse output for encoder emulation.
  • Multiple programmable outputs.
  • Compact rugged construction.
  • Assimilates direction & encoder inputs
  • Velocity determined to 0.1% accuracy
  • Optional analogue 4-20mA output
  • Measures off all surfaces

General Description

The VLM320 operates optically without contact, and implements the principle of the spatial filter by means of the use of a CCD sensor. Spatial filter is the generic term used to describe a measuring principle for the non-contact determination of the velocity and length of moving materials. The spatial filter is based on the filtering effect of grid-like structures (grid modulation).

The function of the VLM320 can be described as follows: The object to be measured is reproduced throug
h the objectiveonto the CCD sensor.

The CCD sensor is operated as an optical grid (no image pickup). The object to be measured is illuminated
by an integrated light source (LED). External light disruptions are effectively suppressed with this method.
When the object is moved, a signal frequency is generated due to grid modulation. This frequency is proportional to the velocity at which the object is moving. The device measures the signal frequency and converts it to a velocity value.
There are several control circuits that enable automatic adjustment to the most varied of materials (material surface  structure and brightness).