Burkert says that this means that it is less affected by dirty media than other flow measurement devices for water. In addition, Burkert adds that the 8081 has a wide dynamic measurement range, a low pressure drop, and does not require long, flow conditioning tubes before and after its inlet and outlet.
According to Burkert, the brass-bodied 8081 flow transmitter is intended for the measurement of water flows that may be slightly charged with contaminants. The design of the device delivers ‘swirl-free’ flow, which results in homogeneous velocity distribution; consequently, no inlet and outlet zones are required with the 8081 unit. Moreover, because the flow over the reflector surface is optimised in the 8081 design, the settling of dirt particles is prevented. This means that the device is non-sensitive to coating as a result of particulate build up; a feature that ensures long term stability and high reliability from the transmitter.
Burkert adds that the measuring system of the 8081 is based on the ‘Transit Time’ principle, integrating two piezoelectric sound transducers that operate with both the downstream and upstream flow through the device. When the signal is against the flow its propagation time is longer compared to the downstream ultrasound signal. The difference in traveling time between these signals is directly proportional to the flow speed and is used to calculate the volume flow.
The 8081 is available in five sizes, for pipe diameters from DN15-25, and flows from 0.06 l/min up to a maximum of 200 l/min. Depending on the version chosen, the transmitter features either a pulse output or a pulse output and a 4-20 mA current output; electrical connection is via a 5-pin M12 fixed connector.
www.burkert.co.uk
