Piston-Type Switches: Low Pressure Drop Info

The key to the excellent flow qualities of the FS-150 and FS-380 Series flow switches is the dual diameter internal bore. At flow rates below the actuation point, the fluid passes around the piston and metering disc within the "metering bore." As fluid flow increases past the actuation point, the metering disc enters the "flow bypass bore" where the increased diameter provides generous flow paths. The result is a low pressure drop for high flow rates and less susceptibility to fouling.