Level Measurement · Glossary

What is Guided Wave Radar?

Symbol: GWRprobe guided microwaveLevel Measurement

Guided wave radar sends microwave pulses down a rod, cable or coaxial probe and measures the echo from the liquid surface.

Guided Wave Radar Explained

The probe concentrates the signal, so GWR works with low dielectric liquids, foam, vapour and narrow chambers. It can also see the interface between two liquids.

Probes touch the process, so coating and build up matter. Coaxial probes are most sensitive but easiest to block.

Guided Wave Radar Formula

d = c × t ÷ 2

c	speed of light, corrected for vapour if needed
t	round trip time of the pulse

Guided Wave Radar: Typical Values

Probe types	single rod, single cable, twin, coaxial
Interface	possible with clean separation and a lower εr upper layer

Calculators for Guided Wave Radar

CalculatorRadar Level CalculatorFree online calculator with formula and worked example.CalculatorRadar Level Dielectric CalculatorFree online calculator with formula and worked example.CalculatorInterface Level CalculatorFree online calculator with formula and worked example.

Free Downloads

Free downloadLevel Transmitter Datasheet Template in ExcelFree download in Excel and PDF.

Frequently Asked Questions

What is Guided Wave Radar?

Guided wave radar sends microwave pulses down a rod, cable or coaxial probe and measures the echo from the liquid surface.

GWR or non contact radar?

GWR for low dielectric, foam, chambers and interface; non contact for sticky, corrosive or large tanks.

Why is GWR good in bridles?

The chamber guides the signal and the probe ignores the chamber wall, so mounting is simple.

Learn more on the blog

Guided wave radar vs non contact radar

A practical guide on instrumentationblog.in with more detail on guided wave radar and how it is applied on real plants.

Read Full Article

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