Brass Inline Water Flow Switch – G1/2″ Inlet / G3/8″ Outlet | IP65 | Reed Switch Type
Overview
Engineered for durability and reliability, this solid brass inline water flow switch is purpose-built for water flow detection and equipment protection in plumbing, heating, and fluid control systems. The robust all-brass construction — reinforced with stainless steel mounting screws — makes it an ideal upgrade over plastic-bodied switches in applications where pressure, temperature, or media demands a tougher build.
With its G1/2″ male inlet and G3/8″ male outlet, this flow switch is designed for easy inline installation and integrates seamlessly into existing pipework. Rated IP65 for dust and water resistance, it performs reliably in wet, outdoor, or semi-industrial environments where moisture exposure is a concern.
How It Works
This flow switch uses an internal magnetic reed switching mechanism to detect the presence or absence of water flow:
- When water flows through the body at or above the trigger flow rate, the internal mechanism is displaced, activating the reed switch and outputting an “ON” signal to the connected control system — allowing pumps, heaters, solenoid valves, or other equipment to operate.
- When water flow stops, the reed switch returns to its default state and outputs an “OFF” signal, shutting down connected equipment and protecting against dry-run or no-flow damage.
The result is a fast, clean, and repeatable digital switching action that integrates directly with PLCs, relay boards, microcontrollers, or any standard control system.
Key Features
- Full brass body construction – Superior strength, pressure resistance, and corrosion resistance vs. PP or plastic switches
- Stainless steel securing screws – Added structural integrity and resistance to rust and loosening over time
- G1/2″ male inlet × G3/8″ male outlet – Dual-size threaded ports for flexible installation in mixed-size pipework
- IP65 protection rating – Fully dust-tight and protected against water jets; suitable for outdoor and wet environments
- Reed switch technology – Reliable, low-maintenance flow detection with no moving electrical parts in the flow path
- 0.5A overload current rating – Safe, signal-level switching for integration with relay or control board circuits
- Compact, robust form factor – Dense brass block design resists vibration and mechanical stress in high-pressure lines
Specifications
| Parameter | Value |
|---|---|
| Item Number | jhfW4-ZW |
| Body Material | Brass |
| Screw Material | Stainless Steel |
| Inlet Thread | G1/2″ Male |
| Outlet Thread | G3/8″ Male |
| Protection Level | IP65 |
| Overload Current | 0.5A |
| Switch Type | Reed Switch (Magnetic) |
Applications
- Electric water heaters (instantaneous & storage type)
- Boiler and heating system flow protection
- Pump dry-run prevention systems
- Solar water heating controllers
- Industrial process flow monitoring
- Water purification and RO filtration systems
- Cooling water circulation control
- Hydraulic and pressure system monitoring
Why Choose Brass?
| Feature | Brass Flow Switch | PP Plastic Flow Switch |
|---|---|---|
| Pressure Resistance | ✅ High | ⚠ Moderate |
| Temperature Tolerance | ✅ Wide range | ⚠ Limited |
| Corrosion Resistance | ✅ Excellent | ⚠ Moderate |
| Mechanical Durability | ✅ Industrial-grade | ⚠ Consumer-grade |
| Lifespan | ✅ Longer | ⚠ Shorter under stress |
| Suitable for High Pressure | ✅ Yes | ⚠ Limited |
