Heat
Water
Accuracy

Posted on Friday, December 4, 2020 by Michael La Cour

Age is just a number – and the latest numbers are good

In sample tests from 2019, 100 % of water meters and 91,8 % of heat meters obtained operation extension – despite having been in use for up to 27 years!

Over time, the moving parts of mechanical meters inevitably wear down. The meters become more imprecise, and let more unaccounted water flow through the system. And water that isn’t accounted for, isn’t paid for.

The most recent tests from our accredited labs show that static ultrasonic meters keep measuring correctly for years upon years – unlike most of their mechanical counterparts. The results make it clear that utilities can escape the vicious cycle of endlessly replacing aging mechanical meters to minimise loses by making the jump to ultrasonic.

Ultra-solid, ultrasonic performance

Danish water utilities are committed to establish a control system that ensures meters in operation do not exceed the permitted usage tolerances. For this purpose, the utilities divide their meter populations into lots, take down meters from said lots on the basis of sample tests, and send these to be controlled at an accredited laboratory such as Kamstrup’s.

Over the span of 2019, we performed sample tests on 10 lots of static ultrasonic meters. The number of meters in a single lot may vary, as it’s up to the individual utility to determine the size of each of their lots. The 10 lots, which we sample tested, constitute 176 meters in operation. And – unsurprisingly to us – the tests concluded that ultrasonic meters are more precise for much longer than mechanical ones.

Ultrasonic meters showed stability as 98.3 % lay within the limit value of ±2 % measurement inaccuracy, set by the Danish Safety Technology Authority. 57.1 % of the mechanical meters achieved the same level of stability.

All in all, 80 % of the 176 represented ultrasonic meters obtained an operation extension of either 6 or 9 additional years, whereas just 9.4 % of the mechanical meters managed to receive a similar extension. The remaining 20 % of the ultrasonic meters obtained an extension of another 3 years.

In other words: not a single one of the tested lots failed to pass the control and achieve operation extension – despite the fact that several of the ultrasonic meters were between 6 and 11 years old. The mechanical counterparts, on the other hand, exhibit a decrease in accuracy proportional to the age of the meters.

Outstanding and outlasting

During 2019, we also controlled ultrasonic flow sensors for heat meters. We sample tested 98 lots constituting a total of 2058 meters in operation, and here the results were equally impressive – if not more.

The ultrasonic sensors clearly showed stability as 98 % of the tested meters lay within the limit value of ±3 % measurement inaccuracy, set by the Danish Safety Technology Authority.

The results of the control ultimately lead to 91.8 % of the represented ultrasonic sensors obtaining an operation extension of 6 to 9 years. This is particularly noteworthy, since several of the ultrasonic sensors were between 12 and 27 years old. Ultimately, the results were good enough to stay in operation for 94 of the 98 lots.

Once again, the reliability, precision, and long-term stability of the ultrasonic principle has been documented. The fact that the tested ultrasonic static meters only get older and more used, but continue to pass the control tests with flying colours, speaks volumes about their long-term usability and value. Their long lifetime and continuous accuracy ensures the lowest possible costs for the consumer, the water utility, and the environment while securing the water utility against an always creeping billing loss at the same time.

In case you’d like to read the full reports of our tests, you can download them here:

Heat meter sample report

Water meter sample report


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