by Albrecht Truter
Sometimes it is easy to think that a portable instrument is a compromise in terms of testing accuracy relative to a benchtop instrument. In the case of Pamas instrumentation that is certainly not the case!
The Pamas S40 is a portable liquid particle counter that meets the same ISO 11171:2016 calibration standard as the benchtop SBSS. The same sensor is used in both instruments.
Why then would you consider the benchtop SBSS or the portable S40?
The advantage of the SBSS is that is more flexible in terms of the range of liquids it can measure in one instrument. Due to the SBSS syringe sampler with pressurisation it can cope with low viscosity liquids like diesel (or even water with the correct calibration!) up to high viscosity gear oils at1600 cSt.
The SBSS has a low dead volume which means only a little sample is required per measurement, user selectable from 1 to 10 ml typically. a Total sample volume 25 – 50 ml is recommended depending on the measurement settings. The SBSS also features integrated sample preparation like vacuum degassing & magnetic stirrer.
The S40’s main advantage is that it can be used in the field on site as it has a build-in battery. Of course, it works just a well on the bench in the lab. It also has the option of inline, pressurised sampling of live hydraulic systems at up to 420 bar.
A S40 is specifically configured for diesel or oil and cannot measure both on one instrument. Hence the availability of the S40 Fuel, S40 Lube oil etc… In batch mode (sampling from a bottle) it requires more time and fluid for flushing and sampling than SBSS. So in cases where large numbers of samples need to be tested daily ( > 50 per day)the SBSS is the better choice.