ABB Vertical Measurement PFCL 201 Measuring principle of the load cell

Compression

Compression is the total reduction in load cell height when the load is increased from zero to the rated value.

The total reduction of the load cell height when increasing from zero to the rated value.

Measuring principle of the load cell

The measuring principle of the load cell is based on the Pressductor® technology and

the fact that the magnetic permeability of magnetic materials changes under mechanical stress.

The load cell is a thin film machined on the load cell. The primary and secondary

windings are wound at right angles through four holes in the load cell.

The primary winding is powered by alternating current, which generates a magnetic

field around the primary winding. Since the two windings are wound at right angles to each other,

no magnetic field is generated around the secondary winding as long as there is no load on the load cell.

When the sensor is subjected to a mechanical force in the measuring direction,

the propagation of the magnetic field changes to encircle the secondary winding,

generating an alternating voltage in this winding.

The control unit converts this alternating voltage into a DC voltage proportional to the external force.

If the measuring force changes direction, the sensor signal also changes polarity.

Mounting arrangement

When choosing a mounting arrangement, it is important to remember to place the load

cell in a direction that provides sufficient measuring force (FR) to achieve the highest possible accuracy.

There is no specific correct orientation for the load cell; it should be placed in the direction

best suited to the application, taking into account the location of the screw holes.

It is also possible to mount the load cell by suspending the roll below the load cell.

The load cell has the same sensitivity in tension and compression, 

so the load cell can be mounted in the easiest way possible.

Typical mounting methods are horizontal and inclined mounting.