Digital position readouts from BW Electronics

Welcome! DROs from BW Electronics Using digital position readouts Prices and ordering information

The 391 single-axis readout

A member of the 300 series of DROs from BW Electronics, the new 391 single-axis readout combines features of the 362 clip-on sensor with those of the advanced 332 measuring readout display. Designed to be movable between machines, it has a maximum 1200mm 48" measuring range, a clear 0.3" red LED display to ±9999.99mm or ±999.995", and status indicator LEDs. Its features include radius/diameter working, the ability to set two independent datum points, and the possibility of pre-setting positions at any time. The 391 readout requires a 9V dc unregulated power supply, at 150mA max, 10mA typical (that is, the same type of power supply as is used for the MPS2).

How the sensor works

All the sensors from BW Electronics use a similar measuring method, based on an extending stranded stainless-steel wire, much like a tape measure. The measuring wire is wound around a small drum inside the sensor, which also has a restoring spring. As the wire is pulled out or returned under the spring tension, the wire winds off or on the drum. The drum has a thread cut on its outside diameter to ensure the wire winds cleanly on and off, with no overlapped turns. Attached to the drum is a rotary optical encoder that measures the rotation; signals from the encoder are counted to give the distance moved.

This method of measuring makes it particularly easy to fit sensors on smaller machine tools.

• The measuring wire has minimal cross-sectional area, so it can be squeezed into very restricted spaces.
• Being flexible, the wire can be taken around pulleys to change direction, avoid obstacles etc.
• The measuring wire can be taken around curved objects such as a rotary table to measure angles.

BW Electronics, 12 Mussons Close, Corby Glen, Grantham, Lincolnshire, NG33 4NY, Great Britain
Tel/fax: +44(0)1476-550826
e-mail: sales@bwelectronics.co.uk