1 This International Standard specifies a liquid automatic particle counting procedure for determining the particle size distribution and number of particles present in hydraulic fluid bottle samples taken in accordance with an approved procedure. Measurements are generally made with the particles suspended in the original liquid.
2 In general, this method of quantitative analysis is suitable for monitoring
— the contamination level in hydraulic systems;
— the progress of a flushing operation;
— support equipment and test rigs;
— packaged stock.
3 The use of this technique is only applicable to clear, homogeneous single-phase liquids; the presence of a fluid interface will obstruct the light beam and give false signals.
ISO 11500:1997 history
2022ISO 11500:2022 Hydraulic fluid power — Determination of the particulate contamination level of a liquid sample by automatic particle counting using the light-extinction principle
2008ISO 11500:2008 Hydraulic fluid power - Determination of the particulate contamination level of a liquid sample by automatic particle counting using the light-extinction principle
1998ISO 11500:1997/Cor 1:1998 Hydraulic fluid power - Determination of particulate contamination by automatic counting using the light extinction principle; Technical Corrigendum 1
1997ISO 11500:1997 Hydraulic fluid power - Determination of particulate contamination by automatic counting using the light extinction principle