The design of smart electric valve actuators remained near stagnant for many years with most designs relying on the traditional cam and micro-switch solution to stop the motor. So-called design improvements often saw small changes to improve the design of the cams and switches, or the introduction of a brushless motor, for example, rather than a more radical change to the basic principals of operation.
Recent advances have seen a move towards digital control of the actuator’s position via digital magnetic positioning technology, which offers not only improved accuracy as it is digital but also a non-mechanical system which has
Whilst the elimination of mechanical components hints at improve total life cost as there as fewer parts that can fail, it is the switch to control of the functionality of the electrical actuator by software that is the more significant benefit. Employing brushless motors from the start, actuators like the AVA actuator available from Actuated Valve Supplies in the UK, recently tested by J4C-S have embraced modern technology and offer a dazzling list of standard and optional features, all controlled by software.
Combining a user interface comprising of a bright OLED screen and external push buttons, users not only have useful operational information displayed on the screen but have the ability to either control the electronic actuator locally, more commonly referred to a ‘local control’, but can make minor adjustments to several useful operational parameters that separates valve actuators like the AVA actuator from most rivals in its class, from a user perspective.
Features such as speed control, external adjustment of zero and span (open and closed positions) which in electric actuators with cams and switches requires the cover to be removed to access the switches, and external setting for 3 positions become standard features in software-driven actuators rather than ‘factory specials’ from manufacturers still using the original cam and switches design.