BS ISO 11943:2018 pdf download

BS ISO 11943:2018 pdf download

BS ISO 11943:2018 pdf download.Hydraulic fluid power — Online automatic particle- counting systems for liquids — Methods of calibration and validation
1 Scope
This document establishes methods to:
— validate equipment used to prepare secondary calibration suspensions for automatic particle counters;
— perform online secondary calibration of automatic particle counters;
— match two or more online particle counters, i.e. to count the same number of particles at a given size by two APCs associated on line;
— validate online particle counting systems with and without online dilution as used, for example,to measure the filtration efficiency of a hydraulic filter as described in the multipass filter test in ISO 16889.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 4021, Hydraulic fluid power — Particulate contamination analysis — Extraction of fluid samples from lines of an operating system
ISO 5598, Fluid power systems and components — Vocabulary
ISO 11171:2016, Hydraulic fluid power — Calibration of automatic particle counters for liquids
ISO 12103-1, Road vehicles — Test contaminants for filter evaluation — Part 1: Arizona test dust
ISO 16889, Hydraulic fluid power — Filters — Multi-pass method for evaluating filtration performance of a filter element
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5598 and ISO 11171 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at
— ISO Online browsing platform: available at
4 Units of measurements
The international system of units (SI) is used in accordance with ISO 80000-1.
Throughout this document, the use of µm, [or µm(b) or µm(c)] means that particle size measurements are carried out using an automatic particle counter that has been calibrated in accordance with either ISO 11171 or this document and particle size reported as defined in ISO 11171.
5 Test equipment
5.1 Liquid automatic particle counters, requiring either calibration or verification, or a particle counter with two independent sensors.
5.2 A reference particle counter, calibrated with a reference material in accordance with ISO 11171.
5.3 ISO Medium Test Dust (ISO MTD) concentrate, in accordance with ISO 12103-1, category A3,dried at 110 °C to 150 °C for at least 1 h and for use in the test system, mixed in the test fluid, mechanically agitated, then dispersed ultrasonically with a power density of 3 000 W/m 2 to 10 000 W/m 2 .
NOTE This standard test dust is used for filter test purposes in ISO 16889.
5.4 Test fluid, as specified in ISO 16889.