How to use the PS (PSA) classifications

The PSA classifications take a different approach to other systems and reflect common industry practice when specifying, ordering or selecting equipment. They are intended to ensure that machines are matched as well as possible to end-user needs.

To be flexible, classes can be easily fine-tuned while minimising the chances of confusion. So class criteria are adjusted to meet changing needs and equipment design parameters over time.

The PSA classification principles

Each group of classifications has been designed around a common set of principles, to ensure they are easily understood and applied.

Equipment is classed according to the most appropriate criteria. These include:

• Operating weight: excavators, dozers, graders, rollers, trenchers
• Operating capacity: wheel loaders, crawler loaders, skidsteers, telescopic handlers
• Payload capacity: dump trucks, scrapers, site dumpers
• Dig depth: backhoes
• Width capacity (paving/profiling): pavers, profilers

Each type of equipment was initially classed using a consistent range of measurement increments, as follows:

1 increments up to 5
2.5 increments, 5-15
5 increments, 15-40
10 increments, 40-100

Larger increments apply for larger equipment items (such as mining excavators, trucks, etc)

Class nomenclature is consistent and easy to understand, so that end users always know what size of machine a class describes.

Thus, rather than “Class 1”, “Class 2”, “Class 3,” etc, PSA classes use names that actually relate to the size or capacity of a machine.

Thus a Class 20 excavator is in the 20 tonne range (20-25 tonnes), a Class 35 articulated dump truck is in the 35 tonnes payload range (35-40 tonnes) and a Class 6 Wheel loader is in the 6000 kg operating capacity range (6000-8000 kg).

Class names always reflect the actual numerical values used, ensuring end-users can easily determine from the class name the size of the machine being described.