Valve Device (VD)
The Eltav Valve Device (VD) is the basic component of the system - it is installed on top of the monitored valve or actuator. A mechanical stem attaches the VD to the axle of the valve or actuator. The VD sensor measures the angle that corresponds to the opening of the valve (in degrees or percentage). The valve position is then transmitted by an embedded bi-directional transceiver that is inside the VD. This wireless transmission is based on the standard Zigbee protocol. In addition, a dedicated Low Frequency (LF) receiver in the VD, supports communication with the hand-held maintenance and provisioning device (the Operator Device). Customized mounting brackets are available to support all types of linear and multi-turn valves, allowing accurate position indication in terms of open percentage.
The VD is a smart device with three integrated processors that continuously maintain the fastest response time, high communications reliability, and optimal energy consumption for a long battery life (5 years with a set of two 1/2AA batteries). The compact enclosure of the VD complies with the process industry environmental requirements. The Eltav system provides real-time information about the valve status directly into the control process. This breakthrough solution reduces failure and risk in the plant while increasing safety and yield – all for a fraction of the cost of traditional wired systems.