Electronic tachometer
Page 61
If you've noticed an error in this article please click here to report it so we can fix it.
An electronic tachometer, known as the type VII has been introduced by Barbie Engineering which can be fitted with any one of the range of proximity sensors marketed by the company.
Projections on a moving or rotating shaft or object are detected by the sensor. Electrical impulses are generated and their frequency is measured by and indicated on a meter in terms of speed or rate. For example, bottles of liquid on a conveyor can be detected and the rate of flow indicated continuously in bottles/hr.
Speed of movement can also be recorded and the recording system can be used to give a highor low-speed alarm or to control other functions. The sensors exert no load on the moving parts, which can be of non-ferrous metal or even non-metallic.
With the exception of the indicating meter all the circuits are solid state using transistors, while the sensors are generally encapsulated in epoxy resin and are waterproof. There are no mechanical parts to wear and no maintenance is needed. The indicator may be located in any convenient place.
A special version of the sensor is designed. for measuring speeds in explosive atmospheres. This sensor is certified as intrinsically safe when used in conjunction with Zener diode safety barriers.
Made by: Barbie Engineering, 10 Beresford Av, Twickenham, Middlesex.