Flow switch, IP43 enclosure,

Johnson F61 Series Flow Switch

The F61 Series Flow Switches are Single-Pole, Double-Throw (SPDT) flow switches used on fluid lines carrying water, ethylene glycol, or other fluids not classified as hazardous. They can be wired to energize one device and deenergize another device powered from the same source when fluid flow either exceeds or drops below the set flow rate.

Features:

Stainless steel paddle has three segments for use in pipes from 1 in. to 3 in. (25 mm to 75 mm) diameter
Paddle segments can be removed or trimmed as needed
F61KB-11 and F61MB-1 include a 6 in. (152 mm) paddle for pipes 4 in. to 6 in. (102 mm to 152 mm)
Gold-plated contacts on F61MG-1 reduce intermittent contact problems in low-voltage and low-current circuits