TIP-5

Installation and Calibration

Once load cells are installed in an application the accuracy specification is normally affected.

Minimize the influence of attachments by following the manufacturers installation recommendations.

Long horizontal runs for piping to your scale provides the best flexibility and repeatability.

Consider the rigidity of any vertical connection and make it as flexible as possible.

Most flex coupling are designed for free movement horizontally and are quite difficult to compress.

Picture yourself as the scale and how the connections would affect you.

When installing couplings they should slide into a space = the manufactured coupling length then tightened.

Do not compress couplings or stretch to close a gap this greatly affects accuracy and repeatability.

Weights are accurate and indicate areas of mechanical influence when randomly placed on your scale.

In some instances like large silos, applying weights is not practical.

Electronic calibration or simulation to factory specifications is often done for these applications.

The electronic calibration can be adjusted to a known load such as a transfer of product from a truck.

Electronic calibration uses the factory load cell Mv/V specifications to set system accuracy.

With minimal mechanical influences typically you can expect 0.25% or better.

Some indicators/controllers have menu items to enter the load cell capacity and rated Mv/V.

For other instruments a load cell simulator can be used with multiple Mv/V settings for calibration.

Electronic calibration can be tested by filling with a known quantity of water or for dry products fill/dump and weigh.