A flow transmitter is a device used as a means of measuring the flow of a specific substance, usually liquid, through a series of pipelines or tubing. These measurements begin as electrical signals, measuring anything from the volume of substance being pushed through the pipeline to the speed at which the fluid is moving. The measurements are converted from electrical signals by the flow transmitter and sent to a designated receiving agent, such as a computer or an automated control station. They are then translated by the flow transmitter to allow control operators to visualize the amount of liquid being transferred through pipelines in order to regulate the flow and ensure that the proper volumes are being transported at all times.

There are many different applications in which a flow transmitter may be required, especially in cases where a flow meter is installed on a piping series but the meter is not clearly accessible to the operator. A flow transmitter may be installed in conjunction with the flow meter to transmit the results the flow meter produces to the control station manned by the operator. The control panel, usually a membrane switch, allows the operator to ensure that the correct amount of volume, flow rate, temperature, and pressure of the material being transferred through the pipeline is maintained.