how it works

Using our advanced system, we ensure that optimum pressure is maintained within the tyres at all times, but how is it done?

air line to axle
air feed in
control box

tyre hose

rotary union

air supply
warning light

stator

air line to axle
air feed in
control box

tyre hose

rotary union

air supply
warning light

stator

feel the pressure

Air pressure is taken from the trailer air supply (air suspension side) through a pressure protection valve. It is then regulated at the control box, set to the desired tyre pressure applicable to the load. Air is then distributed to the axle beams, which act as a correctly pressurised conduit, whilst stationary or in transit as long as it is connected to the air supply of the truck.

PSI market leading system

• Pressure Systems International (PSI) was established in 1993 and has grown to be the number one systems supplier worldwide.

• Automatically inflates as needed, whether the trailer is static or dynamic.

• Can be installed on virtually all commercial vehicle trailer axles worldwide, including; SAF, BPW, JOST (Daimler Chrysler), Schmitz Rotos, ROR & VALX.

• Over 20 years of operating history as the most reliable system on the market with over 1.5 million systems in operation worldwide.

• PSI is used by fleets such as FedEx (Operating the PSI for over 10 years), Walmart (ordered 6500 systems on their new trailers in US in 2017), UPS and Sysco.

• 70% of the top 200 fleets in North America use the PSI system.

The psi system is compatible with most European axle types. Click here to view our axle compatibility matrix.