Four port variable load valve weight system for a brake pipe controlled brake system

A pneumatic system serves as a backup to the electronic system that normally provides load compensation on a railcar truck during both service and emergency applications of the brakes. The pneumatic system compensates for the load railcar bears during service and emergency brake applications whenever the electronic load compensation system fails due to a loss of power or other electrical failure. Ideal for railcar trucks equipped with brake pipe controlled brake equipment, the pneumatic system provides load compensation through use of a four-port variable load valve in combination with a low complexity MC-30A-1 control valve.