Automatic Stainless Steel Mechanical Water Flow Switch – Target Type, NO/NC Contacts, AC125V/250V Rated

Product Overview

This product is a mechanical target-type water flow switch designed for flow detection and control in liquid circulation systems, such as water cooling systems and industrial fluid circuits.

Available models: HFS-25 / HFS-20 / HFS-15

Working Principle

The flow switch operates through a mechanical target (paddle) mechanism and does not require a power supply. It functions as a signal switch and is typically connected to an AC contactor or control circuit.

The unit provides one Normally Open (NO) contact and one Normally Closed (NC) contact.

Electrical Contact Rating (Important)

• AC125V / 3.5A (resistive load)

• AC250V / 2.5A (resistive load)

Note: The voltage ratings above refer to the internal micro switch contact capacity, not the operating voltage of the flow switch itself.

Operating Conditions

• Maximum pressure: < 1 MPa (10 kg)

• Liquid temperature range: 0–80°C

• Recommended use: control circuits or AC contactors (for motors above 500W)

Mechanical Durability

• Micro switch mechanical life: over 1,000,000 operations

Model Specifications

HFS-25

• Thread size: 1 inch (DN25)

• Diameter: 32–33 mm

• Target width: 27 mm

• Target slices: 5

• Available lengths: 150 / 125 / 90 / 60 / 35 mm

HFS-20

• Thread size: 6 points (DN20)

• Diameter: 25–26 mm

• Target width: 15 mm

• Target slices: 3

• Available lengths: 90 / 60 / 35 mm

HFS-15

• Thread size: 4 points (DN15)

• Diameter: 20–20.5 mm

• Target width: 15 mm

• Target slices: 3

• Available lengths: 90 / 60 / 35 mm

Package Includes

• 1 × Water Flow Switch