What is the difference between a water meter and a flow meter?
The answer is that a water meter measures the flow of water. This could be cold water, hot water, drinking water, wastewater and even seawater. For general use, the traditional type of water meter uses a propeller, fan or turbine wheel which is fixed into a pipe which either turns a counter or needle in one direction. Typical water meters normally work in one direction and are not bi-directional.
A counter moves when water passes through the water meter. The counter shows the actual usage or volume of water that has passed through the water meter i.e the total volume or totalized volume.
This could also be called a water meter, but it is normally called a flow meter because it has a dial that moves according to the increase or decrease in flow rate.
Then what is a digital water meter or a digital flow meter?
A digital flow meter is normally a term for a type of product that has a digital display as part of the meter product. The display could be the LED, LCD or even OLED but there is a another meaning to “digital” that has more to do with the outputs generated by the flow meter.
Traditional flow meters have an analog output. Previously, these outputs were pressure-based e.g. 3-15 psi but later an electrical output 4-20mA became more popular. Analog measurements can be converted into digital signals e.g. Modbus, Profibus, Fieldbus, HART etc.
Many different types of flow meters are used for water measurements from the simplest low-cost mechanical types to more sophisticated types of meters which have been designed to measure flow more accurately at different velocities or process conditions. Each flow meter will have its specification which will normally give information on the flow range it can measure as well as the turndown ratio, accuracy and repeatability. For more information on selection of flowmeters contact us at flowmeters.ph
