The Proximity division of Dwyer Instruments has launched a tuning fork level switch, the series TFLS. The TFLS incorporates a piezoelectric crystal that vibrates the fork at its natural frequency.
The switch changes state when the vibration is dampened by sensed material. Featured in the TFLS is user-selectable fail-safe operation of the contacts and LED indication of switch status. The unit is not affected by vibration from conveying systems, motors or the movement of material. It can be mounted in any position and is available with factory-built extensions for mounting on top of the storage vessel.
Series TFLS requires no calibration and with no mechanical moving parts, no routine maintenance is required. It is unaffected by the dielectric constant of the sensed material, making it superior to a capacitance level switch for applications where the dielectric constant is too low, where there is more than one material being used in one vessel, and when material moisture content can change.
The level switch is suitable for level control of powders and fine-grained solids, especially those with a low bulk density.
