Compression Load Cells are those subjected to the load only in the compression direction and are for example used in applications such as silo weighing, automotive weighing platforms, but also in many others in the most disparate environments. Bending Cells, widely used in industrial environments, are also monodirectional.
Traction devices, on the contrary, are those subject to traction only: dynamometers or load cells for overhead cranes or hoppers are widely used.
Bidirectional Load Cells are instead used where the applied force can be both tensional and compressive. Example: moving mechanical parts, such as pistons or, for dynamometers, presses, material testing machines etc... Sometimes the application suggests the purchase of a Bidirectional Cell also for use in one direction only.