Factory Setting:
WPS10-1, WPS10-2: 4-8 psi ;
WPS40-1: operates at decreasing pressure at 30psi.
WPS40-2: operates at increasing pressure at 50 psi and decreasing pressure at 30 psi.
WPS120-1:operates at decreasing pressure at 110psi.
WPS120-2: operates at increase at 130 psi and decreasing at 110 psi