Electricity + Control April 2017

Enquiries:

VEGA

Tel. +27 (0) 11 795 3249

Email: info.za@vega.com

COVER ARTICLE

FEATURES:

• Control systems+ automation

• Electrical protection+ safety

• Flowmeasurement

• Transformers+ substations

• Lighting

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VEGA

are often difficult to implement and may require periods of trial and

error despite the best efforts of plant technicians. Before long, the

manufacturer’s tech is on site servicing the 26 GHz radar.

Small antennas take radar where radar has never gone before:

Amping up a radar sensor’s focus has an opposite effect on its an-

tenna – its size decreases as transmission frequency increases. An

80 GHz sensor, therefore, does not require a large horn to focus its

beam at the measured material.The signals take a narrow beam all

on their own.The saved space makes a huge impact, particularly as

it applies to retrofitting.

There’s a trend in the pharmaceutical and chemical industries

toward batch production. Batching allows operators to produce

seasonal and low-volume products with less financial investment.

Small batches are produced in small vessels, where conventional

wisdom says using radar is impossible due to small process connec-

tions.Thanks to the compact antenna of 80 GHz radar sensors, that

is no longer true, and operators no longer have to sacrifice accurate

measurement in the name of space.

Enhanced resolution measures to the last drop: When the level of

liquid in a vessel gets low enough, 26 GHz radar is unable to distin-

guish the signal returned by the remaining product from that of the

tank bottom, and the user rightly thinks the vessel is empty when it

isn’t.This is the same as the action-movie computer whiz being unable

to ‘enhance’ surveillance footage. Limited resolution presents a natu-

ral handicap to process efficiency. Ultra-focused

80 GHz devices measure liquid down to the last

millimeter in the tank, giving users accurate data

they can use to optimise their processes. It won’t

thwart a terrorist attack or prevent an elaborate

heist, but the enhanced resolution of 80 GHz radars

sensors helps users avoid waste.

Get Focused: Why 80 GHz radar sensors

are the future of liquid level measurement

T

he introduction of 80 GHz radar sensors represents a paradigm

shift in liquid level measurement. Let’s look at all the things an

80 GHz radar sensor can do.

Focused beam avoids obstructions: Increased focus of the beam

angle is the principal benefit of 80 GHz radar instruments; the one

improvement that makes all the rest possible. In every process, focus

is crucial to accurate level measurement, and these new instruments

emit the most focused signals on the market.

With an antenna of the same size, 80 GHz gauges emit a beam

angle of only 3°.This allows them to be used in vessels with internal

installations or heavy build-up on the walls; the focused microwave

beam simply avoids these obstacles as if they aren’t even there.This

is welcome news in chemical and food production, where obtrusive

internals are the norm and space is at a premium.

An exciting benefit of increased signal focusing is the performance

of 80 GHz radar sensors when mounted on ball valves. Historically,

attaching a 26 GHz radar gauge to a ball valve and receiving an

accurate level measurement has been a significant challenge. Ball

valves contain many interior surfaces that reflect radar signals. To

make matters worse, they are often used in combination with a bleed

ring that can create even more signal noise. All of these reflections

make it difficult to discern which signals are generated by the valve

and which are from the product. This confusion forces operators to

turn to instrumentation manufacturers for help, but the best solutions

The focused beam (yellow) of 80 GHz

radar sensors avoid internal agitators that

contact the 26 GHz radar beam (gray).