12
6.1.7 Load cells are to be installed in application machines where there are relatively low
vibrations (=mechanical noise) that might reduce the measured resolution.
Load cells are to be fixed to machine parts that are not linked, to anything else, by
stiff links (like tubes and cables) that might introduce hysteresis in the measure.
6.1.8 All load cell fixing parts, alignment systems and load guiding systems as well as the
metal plate where load cell is fixed, are to be stiff and with enough thickness
relatively to the applied load.
6.1.9 Nothing is to be interposed between the load cell fixing area and the metal plate
where it is fixed
An incorrect load cell fixation with glue under its fixation area, might introduce non
repeatability a non return to zero errors.
6.1.10 The under listed cells need particular instructions:
Series HC7000, HC 2000 and MP:
The force, to be measured, is to be evenly shared onto the top and bottom contact
surfaces in order to avoid additional errors as well as mechanical damages.
Load is to be applied in order to have it aligned with the hole axis: tubes and screws
are advisable to be used as guiding systems with -0,15mm to -0,3mm tolerances.
It is to be applied an axial bearing on top and bottom of the load cell contact
surfaces, to recover the non parallelism and non planarity of the mechanical fixing
(5° is the maximum allowed misalignment).
The top and bottom contact surfaces are to be clean and well machined.
Load cell is not to move from its fixing position because of vibrations and side
forces: it might be necessary to eventually install load cell onto a housing for the load
cell bottom side.
This load cell housing is to have a 0,3mm larger diameter compared to the bottom of
load cell diameter and its highness is not to touch the load cell external metal lid.
All fixing elements, alignment, force guiding and the metal plate where load cell is
fixed are to be stiff and with enough thickness.
Series MD 5000:
The contact on all the surface of the two external bearings (and not only on two
external contact lines) is imperative; the same on the central loading surface.
The cell has to work always as a supported beam never as a restrained beam even
when different dilatation coefficients of the materials and great temperature changes
occur.
Series LCR 200:
The radial load cell (= web tensiometer) is made up by 3 separated parts: the fixing
base, the central measuring body, the lid.
The measuring axis of the cell coincides with the axis of the connector connected to
the axis of the grub screw on the central body (opposite to the connector).
Make the holes and screw them on the structure in which the cell will be settled.
Split the cell in its parts.
Fasten the fixing base by high strength screws.
Assemble the separated parts and position the measuring axis of the cell with the
resultant of the forces to be measured.
Summary of Contents for 500QD Series
Page 23: ...23 ...
