Guided Wave Radar Level Transmitter - NGM

Precision Measurement Regardless of Changing Process Conditions

The NGM delivers direct, precise, and highly reliable continuous level measurement as well as point level detection for almost every liquid or light solid application independent of changing process conditions. It is ideal for small tanks, bypass chambers, stilling wells, tall and narrow nozzles, difficult tank geometries, and in proximity to interfering structures. The NGM offers a fully modular probe design where the probe types are interchangeable without any special tool or welding. Complete galvanic insulation exists between the electronics and the input/output and tank potential to protect against electrochemical corrosion. Dependable measurement is assured with the NGM with its 4-wire design, innovative signal analysis, and disturbance signal suppression.

How It Works

The NGM utilizes Time Domain Reflectometery (TDR), which is also known as Guided Wave Radar. Electromagnetic impulses are generated by the sensor’s circuitry and then propagated along the immersed probe. When the impulses encounter the media, part of the impulse energy is reflected back up the probe to the circuitry. Level is then calculated by using the difference between the time sent and the reflected signal. The resulting signal can then be provided as a 4-20 mA analog output or converted into a freely programmable switching output.


The NGM can measure liquids up to 65 feet and the wetted parts are stainless steel and PTFE. It available in both NPT threaded and ANSI flange versions. The maximum operating pressure is 580 PSIG. The temperature range is from -320 °F to 480 °F. The NGM delivers an accuracy of ± 3 mm or 0.03% of the measured value.