McDonnell & Miller FS6 115600 1" NPT In-Line High Sensitivity Liquid Flow Switch

The McDonnell & Miller FS6-1 (Part No. 115600) is a heavy-duty, high-sensitivity in-line liquid flow switch designed for industrial and commercial applications that demand reliable, instant flow detection. Featuring a snap-acting single pole, double throw (SPDT) switch mechanism, the FS6-1 responds quickly to changes in flow rate, making it a trusted solution for critical system protection.

Its in-line 1" NPT body design eliminates the need for a pipe tee, simplifying installation and reducing the number of connection points in the system. An accessible sensitivity adjustment screw allows technicians to fine-tune the actuation point directly in the field without special tools.

Key Features:

• 1" NPT in-line connection — no pipe tee required
• Snap-acting SPDT switch for instant response
• Adjustable sensitivity: 0.12 to 2.5 GPM flow range
• Maximum operating temperature: 225°F
• Maximum operating pressure: 100 PSI (150# rated body)
• Voltage: 120/240 VAC
• Heavy-duty construction for demanding industrial environments
• Manufacturer Part Number (MPN): 115600

The FS6-1 is ideal for water treatment systems, cooling systems for electronic circuits, compressors, booster pumps, bearing lubrication systems, and any application requiring fast, reliable flow confirmation. McDonnell & Miller, a Xylem brand, has long been a trusted name in flow switches and liquid controls for industrial, commercial, and building systems.