Diverse MF500M+ Manuel de l'utilisateur - Page 8

Parcourez en ligne ou téléchargez le pdf Manuel de l'utilisateur pour {nom_de_la_catégorie} Diverse MF500M+. Diverse MF500M+ 16 pages. Magmeter

Calibration and pipe occlusion

A magnetite sample was used for factory calibration, This is a

cuvette 1cmx1cmx1.5cm packed with magnetite flakes. A force

measurement is recorded with the centre of a long side of the

cuvette 5mm from the centre of the probe measurement

surface (to simulate a pipe wall thickness). This value is taken

for the factory calibration gain and the software assumes that

this value corresponds to an occlusion of 75% in a tube of

40mm inner diameter and 5mm wall thickness.

By measuring the mass of the cuvette the density of the

magnetite flake sample was calculated and compared to the

density of solid magnetite. This gave a packing factor of 48%.

This factor is used in the display of occlusion for solid

magnetite. Calibration settings can be altered using the

<Calibrate> menu. The calibration standard supplied is

designed to mimic the above, measurement should be on the

black side without the label.

The offset has been set to be nominally 0 counts with the

probe held horizontally. In the unlikely event that the offset

needs to be adjusted then this can be carried by adjusting the

potentiometer. Gently peel back the calibration label on the

probe to access the potentiometer. Using a small screwdriver,

clockwise will take the offset negative, anticlockwise will take

the offset positive. Replace the calibration label after

adjustment. Note that the meter's range is nominally 0 to 2047

force units.

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