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Digital density
measurement
redefined

After more than 50 years of incremental
improvements, Anton Paar redefines digital
density measurement and shapes the
future of the technique once again.

  • 1960s

    Digital density measurement invented by
    Prof. Otto Kratky

  • 1967

    First digital density meter built and presented by Anton Paar

  • 1988

    Viscosity compensation of density results

  • 1997

    Concept of a "reference oscillator" introduced in DMA 4500 Classic

  • 2008

    Debut for the first automatic air bubble detection – FillingCheck™ – in the DMA M series

Density Measurement Redefined

In 2015, a density task force was initiated resulting in implementation of a unique measuring method in 2018: the Pulsed Excitation Method (PEM).

  • 2x better viscosity correction than predecessor
  • Best FillingCheck™ ever
  • 8 new patents
  • Numerous add-on features

The Next-Level Density Meter

20 seconds
to 4-digit accuracy,
6-digit accuracy available
30 +
guided
user workflows
Best-in-class
user experience
Best U-View™
ever
Powerful
industry-specific software

1960s

Digital density measurement invented by
Prof. Otto Kratky

1967

First digital density meter built and presented by Anton Paar

1988

Viscosity compensation of density results

1997

Concept of a "reference oscillator" introduced in DMA 4500 Classic

2008

Debut for the first automatic air bubble detection – FillingCheck™ – in the DMA M series

A lot has happened in the world of digital density measurement in the last few years. Since 2018, Anton Paar has launched a revolutionary new measuring principle, the Pulsed Excitation Method, and registered a number of patents.

Read about the individual success stories behind the products.

A new heart,
a new start

The heart of a modern digital density meter is the measuring sensor, a U-shaped tube made from borosilicate glass or metal. It is excited to oscillate at its characteristic frequency, which is directly related to the density of the sample. After Anton Paar’s re-invention of digital density measurement, there are now two excitation methods on the market: conventional and new.

Launched in the1960s

Reachedits limits
Launched in2018
Highestprecision up to the7th digit
2x better
viscosity
correction

Forced
Oscillation
Method

Launched in the 1960s
Reached its limits

Used in conventional density meters

Since the launch of this method by Anton Paar in the 1960s, a constant oscillation of the U-tube has been the state of the art. In this method, the U-tube is forced to oscillate continuously at its characteristic frequency. Over the years, continuous improvements like viscosity correction of the measured results and filling error detection were implemented. However, this technology has reached its limits. In order to advance, Anton Paar’s dedicated research team has rethought this technology from scratch.

Pulsed
Excitation
Method

Launched in 2018
Highest precision up to the 7th digit
2x better viscosity correction

Patented technology exclusively by Anton Paar (Patent AT 516420 B1)

The new patented Pulsed Excitation Method (PEM) redefines digital density measurement. After reaching a stable oscillation, the excitation is switched off and the oscillation fades out freely. This sequence of excitation and fade-out is repeated continuously, creating a pulsing oscillation pattern. By allowing the natural oscillation of the U-tube, and evaluating this oscillation pattern, the instrument gains three times more information than with the conventional Forced Oscillation Method.

Your benefits:

The highest precision

Viscosity insight

More confidence

FillingCheck™ for metal oscillators

Request more information

Forced
Oscillation
Method

launched in the 1960s
Reached its limits

Used in conventional density meters

Since the launch of this method by Anton Paar in the 1960s, a constant oscillation of the U-tube has been the state of the art. In this method, the U-tube is forced to oscillate continuously at its characteristic frequency. Over the years, continuous improvements like viscosity correction of the measured results and filling error detection were implemented. However, this technology has reached its limits. In order to advance, Anton Paar’s dedicated research team has rethought this technology from scratch. The result: The new patented Pulsed Excitation Method.

Clearly
the better way

1point
water
adjustment
Ready to measure from 0 °C to150 °C
Instrument selfdiagnosis
ISO5725

  • Top results – in any situation

    The Pulsed Excitation Method provides unmatched sensitivity and the measuring cell design guarantees stable results unaffected by external influences such as frequently changing users with different filling styles. The instrument monitors the condition of the measuring cell itself and issues a warning in case of potential measuring errors. The latest generation even warns you when the humidity and ambient temperature are not optimal and gives recommendations on how to ensure the maximum lifetime of your instrument.

  • We take credible specifications seriously

    We derive the terminology and definitions of relevant metrological specifications from the ISO 5725 standard. This is not common practice in the density meter business – Anton Paar is the only density meter supplier whose specifications leave no room for doubt. The trueness of our instrument specifications is verified with national standards, traceable to measurements with the hydrostatic balance.

  • Smart glass-drift compensation

    To provide a 4-digit density meter at an unbeatable price required drift compensation without a costly reference oscillator. This requires a one-point water adjustment, a unique feature on the density meter market. The measured oscillation period of water is compared to that of the last adjustment and potential drift is corrected automatically. You are ready for measurement in half the time compared to any other benchtop density meter available.

  • Full-range factory adjustment – now also for metal oscillators

    Density meters with a metal oscillator based on the Pulsed Excitation Method receive a wide-range density adjustment before shipping. This Temperfect™ adjustment is permanently stored along with the density temperature coefficients in the device so that you can simply choose a measuring temperature between 0 °C and 150 °C. You need no manual adjustments – just measure density right away.

Benchtop density meters make use of U-tube technology with two different types of oscillation directions, X and Y, named after their physical movement. Over time, the X-oscillator proved to have technological limitations.

X-oscillator Y-oscillator
Straight parts moving towards each other Oscillation direction Bend of the U-tube moving up and down
Limited accuracy for viscous samples Viscosity influence No limitations over the full range
High error rate with inhomogeneous samples or in case of particles and bubbles Sample condition Particles and bubbles are detected reliably
Accuracy limited to 0.001 g/cm³ Measurement performance Accuracy up to 0.000007 g/cm³

As the technology leader, we always go for the better way. This makes the decision obvious: For the highest precision, only Y-oscillators are used in Anton Paar benchtop density meters.

Learn more

More than
50 years of
experience
in your hand

10x faster
Ready in one second
Maximum life time
The Only intrinsically safe device
3x wider viscosity range

  • Highest robustness and accuracy

    The new measuring cell of our portable density meter series is more rugged and at the same time delivers more accurate results. How is that? The influence of viscosity on the density result is compensated via an intelligent phase transition in excitation of the oscillator. This makes accurate measurements possible in a sample’s viscosity range three times wider than in the past – up to 300 mPa·s.

  • Operated by movement of the instrument

    Via an integrated motion sensor the portable density meter is able to allocate its own spatial position. By a simple move of the instrument you automatically identify sample names in just a second via an RFID (Radio Frequency Identification) interface, start a measurement, and abort it, if necessary. Your second hand stays free to hold you steady when measuring hard to reach samples.

  • Intrinsically safe

    It takes only one piece of paper to prove it – but it needs the whole instrument’s intelligent design and manufacturing to assure it: safety for density measurements in explosive atmospheres. Our intrinsically safe handheld density meters for the chemical and petroleum industry are the only certified option for use in hazardous atmospheres.

  • Replaceable measuring cell

    In the field, sometimes robustness is not enough. With this in mind, we made the measuring cell for our portable instrument replaceable by applying a patented design. Each measuring cell keeps its individual adjustment data safe on a small electronic board, waiting for the moment to be connected to the operating panel. By offering a DIY repair to our customers we can ensure your density meter is ready for use 24/7.

Anton Paar provides a range of portable density meters, including the only intrinsically safe handheld device.

Learn more

10x faster
Ready in one second
Maximum life time
The Only intrinsically safe device
3x wider viscosity range

Free webinar recordings

Go digital – entry to a new and more convenient world

Good Density Measurement™

Petroleum industry: measuring density at key points

3-year warranty

  • Effective January 1, 2020, all new Anton Paar instruments* include repair for 3 years.
  • Customers avoid unforeseen costs and can always rely on their instrument.
  • Alongside the warranty there is a wide range of additional services and maintenance options available.

* Due to the technology they use, some instruments require maintenance according to a maintenance schedule. Complying with the maintenance schedule is a prerequisite for the 3-year warranty.

Learn more

The
broadest portfolio
for laboratories and
production sites

Today’s world requires combined solutions and standardization across departments, plants, and subsidiaries. Anton Paar meets this demand with the broadest portfolio of density meters available: from the only intrinsically safe handheld density meter on the market to the most accurate benchtop density meter.

Find your density meter

But the portfolio does not end there: Numerous sample changers allow you to process up to 96 samples in a row fully automatically, including a heated sample changer for measurements at up to 90 °C.

For the ultimate fusion of your laboratory and production plant, Anton Paar inline sensors measure density, Brix, concentration, API gravity, and other parameters and communicate with the benchtop DMA density meters via our matchmaking features. This connection guarantees correct density results in the lab and at the production line at all times.

Browse process density sensors

Anton Paar density meters are ready wherever high-end density and concentration measurement are needed – across all industries and applications.

The
broadest portfolio
for laboratories and
production sites