Metrosol Limited

Metrosol was established in 2004 by Paul Bramley (St. John’s 1975) to develop precision electronic instruments for the temperature metrology market. The international temperature scale (ITS-90) uses platinum resistance thermometers (PRTs) as interpolating devices between the fixed points on the scale (the melting, freezing or triple points of ultra-pure materials) and requires the resistance of these PRTs to be measured to <±1 ppm (0.0001%). Metrosol has developed some unique and innovative electronics, it has earned a reputation for supplying the most accurate instrumentation to the market through its commercial partner Isothermal Technology Limited. In 2017 Metrosol was recognised with a Queen’s Award For Enterprise: Innovation for its “microK” product, which can measure resistance to <±0.03 ppm (0.000003%). Metrosol continues to innovate and more recently started work on developing the world’s first commercial Johnson Noise Thermometer (JNT). Unlike existing thermometers (which measure a property such as resistance that is affected by temperature), a JNT measures true thermodynamic temperature (the average kinetic energy of the particles in the system) by measuring the exquisitely small noise signal produced by the thermal agitation of the electrons in a conductor. This involved the development of a completely new technique for measuring this signal (patented). The Institute of Measurement and Control recognised the achievement by awarding the Callendar medal to the team. Because a JNT measures temperature “directly” it does not drift as the sensor degrades with time (a serious problem in harsh environment). Also, by measuring true thermodynamic temperature rather than an artefact based scale such as ITS-90, it will facilitate the realisation of the Kelvin following its redefinition in 2019. Our ethos can simply be stated as “uncompromising”, we are always looking for ways to improve measurement performance. We enjoy developing products that meet the challenges of making ever more accurate measurements by collaborating with partners (National Measurement Institutes and commercial organisations) who are acknowledged leaders in their field. We believe that working for Metrosol should be rewarding intellectually, provide opportunities to learn from some leaders in the field and should also be enjoyable. We are a small company, but are always interested in hearing from engineers who might wish to join us as we continue our journey of technical discovery.

We are currently looking to recruit a graduate engineer to work on developing electronics for our Johnson noise thermometer project. We offer summer internships, but have already filled the vacancy for 2025.