Hydraulic fluid power - Determination of the particulate contamination level of a liquid sample by automatic particle counting using the light-extinction principle (ISO 11500:2008, IDT)
This International Standard specifies an automatic particle counting procedure for determining the number and sizes of particles present in hydraulic-fluid bottle samples of clear, homogeneous, single-phase liquids using an automatic particle counter (APC) that works on the light-extinction principle.
This International Standard is applicable to the monitoring of
a) the cleanliness level of fluids circulating in hydraulic systems,
b) the progress of a flushing operation,
c) the cleanliness level of support equipment and test rigs,
d) the cleanliness level of packaged stock.
NOTE 1 Measurements can be made with particles suspended in the original liquid or in a sample of the liquid diluted with a compatible liquid to reduce coincidence error.
NOTE 2 The presence of a fluid interface obstructs the light beam and gives false signals.