- The PCME QAL 181 uses a low-angle forward light scattering measurement principle unique to PCME (see ProScatter™ Forward Scatter). The measured cone of scattered light is larger than normal for light scatter instruments, which provides:
+ Excellent sensing resolution and sensitivity, due to an increased signal-to-noise ratio
+ Reduced cross-sensitivity to changing particle size, allowing a greater range of applications for which the instrument is suitable
- Using tough high-grade components and enclosures, and designed to overcome problems encountered with alternative light scatter technologies, the PCME QAL 181 offers outstanding reliability:
+ No optical fibres, which are prone to degradation in elevated temperatures
+ No moving active measurement parts, ensuring sensing components remain correctly aligned. Alternative technologies require movement of the position-critical detectors for the performance of self checks. The PCME QAL 181 avoids this by introducing a diffuser into the light path, which gives the additional benefit of a true check of the instruments ability to measure scattered light, rather than just attenuated light
- As an approved Particulate Measurement System for compliance monitoring, the PCME STACK 181 is supported by filter audit units which are an approved reference material for conducting quarterly linearity checks as Absolute Correlation Audit (ACA).
- To audit the instrument, the sensor is temporarily removed from the stack and Filter Audit reference “scattering bodies” are inserted onto the PCME STACK 181 measurement zone. The resulting response is measured to ensure linearity and also to provide a reference check that ensures contamination is not affecting the performance of the instrument.