
Flow Transmitters

Flow meters are devices that measure the amount of liquid, vapor or gas that passes through them. Flow meters consist of a primary device, a transducer and a transmitter. After the transducer senses the liquid or gas that has passed through the primary device, the transmitter will create a usable electrical signal that can be transmitted and received by other control devices or instruments. There are several things to consider when selecting a flow meter. The type of media to be measured: liquid, vapor or gas. The flow measurement type: velocity, volumetric or mass. The pressure and temperature of the media. The required flow range and accuracy.
Dwyer Series IEF Insertion Electromagnetic Flow Transmitters are adjustable insertion flow meters that feature electromagnetic technology that accurately and reliably measures fluid velocity in addition to providing several continuous signal outputs. One unit is adjustable to fit pipe sizes from 4 inches to 36 inches and offers several output options including Modbus RTU or BACnet MS/TP communications protocol over 2-wire RS-485 in addition to standard analog, frequency and alarm outputs.
Products
Some of the most common types of transmitters and transducers can be found on pressure instruments. Examples of these include: drop-in well pressure devices and devices that measure the pressure in a pipe or gas chamber. Transmitters and transducers can also be found on flow and speed measurement devices.
What is the difference between transmitters and transducers? The main difference is the way they send data to the monitoring device, like a PLC. In terms of measurement, the transmitter will reference a measuring unit by sending a milliamp signal (such as 4-20 mA). A transducer will reference a measuring unit by sending a voltage signal, typically in volts or millivolts.
Why have the two different types of transmission methods? The method will depend on the application. If the electrical connection in the application travels a short distance, a pressure transducer is the better choice. Pressure transducers are smaller with fewer active electronic components that can be upset by electromagnetic interference. Also, the voltage signals transmitted over longer distances are subject to voltage drop and signal corruption. A transmitter is better for transmitting signals over a long distance.