Also see their technical information guide on tyres https://loadsafe.nz/wp-content/uploads/2020/08/motorhome-tyre-pressures.pdf
Below is an extract from Continental tyre catalogue for Vanco Camper tyres giving suggested tyre pressures versus actual axle weight

A “rule of thumb” as a starting point for tyre pressures is the calculator below
Suggested tyre pressure = (Actual weight on tyre / Tyre rated weight) x Pressure at rated weight
Views: 3141