Latest News

Level Measurement Showdown: Ultrasonic Vs. Radar
Tuesday, May 1, 2018 IST
Level Measurement Showdown: Ultrasonic Vs. Radar

There is nothing like a good old-fashioned competition to keep things interesting.  In the level measurement world, that rivalry is between the two most commonly used measurement 

 
 

instruments: ultrasonic, which uses sound-based measurement, and radar, which uses high-frequency electromagnetic waves to determine distance.  Both ultrasonic and radar level measurement devices can also be used to measure flow rates in all types of open channel flow applications through the addition of a flume or weir.
 
Up until recently, ultrasonic was the unchallenged king of level and flow measurement in the water and wastewater sectors. But things are changing.
 
“The benefits of ultrasonic are that it is cheap, has low power consumption, is well developed and understood, and is basically the incumbent,” explained Oliver Grievson, a flow compliance and regulatory efficiency manager at Anglian Water Services. “But it is subject to interferences when it’s not monitored closely. This is where the potential for radar comes in.”
 
So which technology is best? Water Online examines how they compare in price, effectiveness and versatility, setup and use, and familiarity.
 
Price
 
Radar technology isn’t new — it has been on the market for nearly 20 years. But up until a few years ago, it was significantly more expensive than ultrasonic, causing most to stick with ultrasonic.
 
“Radar started dropping in price about three to four years back,” said Richard Lowrie of Krohne, an instrumentation manufacturer that sells both ultrasonic and radar instruments. “Radar has been streamlined; a lot of the things that were unnecessary have been trimmed for simpler application and to reduce the price.”
 
The average ultrasonic level measurement instrument costs $500 to $2,000. Radar level measurement instruments used to cost up to $4,000 but now have dropped down to $1,000 to1,200 on average, putting the two instruments at a nearly level playing field in terms of cost.
 
“People should still look at ultrasonic because it is still less expensive; a high-end ultrasonic will cost the same as a low-end radar,” Lowrie explained. “But I think the radar will keep dropping in price because people want the technology.”
 
Effectiveness And Versatility
 
One factor in determining which instrument is best is the intended application. Nicholas Paradiso, a consulting engineer with CDM Smith, recommends radar level measurement instruments to his clients that work in wastewater because oil, grease, and other coatings can sometimes interfere with the accuracy of ultrasonic measurement instruments.
 
“Any application where you aren’t dealing with 100% liquid, we would want to use radar over ultrasonic, because radar can see through solids better,” Paradiso explained. “But this is only really relevant in wastewater and not water treatment, unless you are dealing with a chemical tank.”
 
Dust, foam, and cobwebs can also present problems for ultrasonic level measuring instruments, and measurement accuracy can be affected by wind, temperature, and snow in outdoor tanks.  Radar doesn't have these limitations, said Anglian’s Grievson.
 
“If the instrument isn't cleaned, which is a common problem, or there is foam, direct sunlight, or other difficult conditions, this is where radar has a benefit,” he said.
 
Operations that use silos, large wells, or oversized tanks may also benefit from radar, which has a longer range.  Typically, an ultrasonic instrument can get an accurate return signal from a maximum of 60 feet away, while a radar instrument can get a return at up to 300 feet. However, this large range isn’t always necessary.
 
“In the water and wastewater industry, a lot of times ultrasonic’s range is suitable,” said Krohne’s Lowrie. “Normally you are dealing with 30- to 40-foot tanks at a wastewater facility. It could be considered overkill to use radar in some applications.”
 
Setup And Use
 
Complexity is also a consideration when it comes to selecting between ultrasonic and radar.
 
Ultrasonic meters have a shorter deadband ­— a minimum distance they have to be above the liquid surface — which can be limiting. But setting up a radar instrument isn’t as simple as setting up an ultrasonic instrument.
 
“With radar, when mounting the actual instrument, I’ve noticed that there are very specific distances you have to have it away from other equipment,” CDM Smith’s Paradiso pointed out. “You may also need to provide a metal plate above it, or the radar waves won’t reflect back properly.”
 
Lowrie feels ultrasonic level meters are also slightly easier to use.
 
“It is just simpler technology,” he says. “But I think radar has a wider range of applications.”
 
Familiarity
 
Despite the benefits of radar, Paradiso believes ultrasonic will stay in the lead for a while.  This is because level measurement devices last 10 to 15 years, and aren’t likely to be replaced often.  While Paradiso does believe radar devices are the future, he doesn’t recommend switching unnecessarily.
 
“If it isn’t broken and is still working, don’t mess with it,” Paradiso suggested. “There are other things that could be done to the plant aside from just going around and replacing all of your instruments.” 
 
There is also some hesitation in the industry to try radar measurement devices because they are not as well known.
 
“Most of the industry is familiar with ultrasonic — it isn’t black magic as radar technology is thought of by some to be,” said Lowrie.
 
Grievson feels more education is necessary on radar use in both level and flow measurement before it can surpass ultrasonic. In the United Kingdom, where Grievson is located, few companies have promoted radar level measurement devices for flow measurement, as many ultrasonic level measurement companies have. This step will help the technology flourish.

 
 
 
 
 

Related Topics

 
 
 

Trending News & Articles

 Article
Tata Harrier’s 7-seater Version H7X Will Be Quite Different – Report

Tata Harrier’s three-row seat version in works, details out  

Recently posted . 2K views . 0 min read
 

 Article
How to make you car as silent as a Rolls Royce inside

Rolls Royce cars are extremely luxurious. While there are many expensive pieces of equipment in Rolls Royce cars, their most relaxing feature is the silence that ...

Recently posted . 2K views . 2 min read
 

 Article
India's Top 5 Mobile Charger manufacturer Brand 2019

The following list of India's Top 5 Mobile Charger manufacture Brand 2019  

Recently posted . 2K views . 0 min read
 

 Article
Mahindra XUV300 vs Maruti Brezza, Ford EcoSport, Tata Nexon – Price

XUV300 is the latest entrant in the compact SUV segment.

Recently posted . 2K views . 0 min read
 

 
 

More in Electronics & Gadgets

 Article
Honda CB300R vs Kawasaki Ninja 300, RE 650, KTM 390, Bajaj Dominar, BMW 310

The new Honda Cb300R enters a segment commanded by the likes of the KTM 390 Duke, BMW G 310 R, Bajaj Dominar, Kawasaki Ninja 300 and Royal Enfield Interceptor 650.<...

Recently posted. 1K views . 1 min read
 

 Article
Eco-Marathon: This car averages around 250 kmpl – check details here

Students run their energy- and power-efficient cars at the Shell Eco-marathon, part of Make the Future  

Recently posted. 957 views . 0 min read
 

 Article
Mahindra XUV300 safety features detailed officially – Video

Mahindra XUV300 which shares its platform with SsangYong Tivoli will come with segment first seven airbags.

Recently posted. 1K views . 0 min read
 

 Video
10 Cool Toys Every Kid Needs



Recently posted . 1K views
 

 Video
Innovations



Recently posted . 1K views
 

 Reviews
Difference between a tubeless tyre and ordinary tyre



Recently posted . 1K views . 12 min read
 

 Article
WhatsApp Co-Founder Brian Acton's Message to Followers: It Is Time to Delete Facebook

Amid the criticism against Facebook for allowing misuse of data collected by Cambridge Analytica, WhatsApp co-founder Brian Acton has told his followers on Twitter ...

Recently posted. 815 views . 3 min read
 

 Article
Top 5 Best USB Phone Charger

A good USB charger will power your phone as fast as it and your cable allow. After testing 15 power adapters this year, it’s clear that the HGD 2.4 Amp Dual U...

Recently posted. 1K views . 2 min read
 

 
 
 

   Prashnavali

  Thought of the Day

"It's always best to have a positive outlook on life, it's easy to see all the bad around you, but there's always good in the world, be thankful you are alive to breathe, to love, to laugh, and to enjoy all the wonders life has to offer."
Anonymous

Be the first one to comment on this story

Close
Post Comment
Shibu Chandran
2 hours ago

Serving political interests in another person's illness is the lowest form of human value. A 70+ y old lady has cancer.

November 28, 2016 05:00 IST
Shibu Chandran
2 hours ago

Serving political interests in another person's illness is the lowest form of human value. A 70+ y old lady has cancer.

November 28, 2016 05:00 IST
Shibu Chandran
2 hours ago

Serving political interests in another person's illness is the lowest form of human value. A 70+ y old lady has cancer.

November 28, 2016 05:00 IST
Shibu Chandran
2 hours ago

Serving political interests in another person's illness is the lowest form of human value. A 70+ y old lady has cancer.

November 28, 2016 05:00 IST


ads
Back To Top