PF3W521-12-2: Precise Sensing, Reliable Guardian! Piston-Type Flow Switch Empowers Safe Monitoring of Fluid Systems

In fluid systems such as cooling, lubrication, and water treatment, real-time flow monitoring is crucial for preventing equipment dry-running, blockages, or pump cavitation. The PF3W521-12-2 piston-type flow switch, with its reliable mechanical structure, accurate set point, and durable materials, provides a cost-effective flow monitoring and protection solution for various industrial equipment.Core Product Advantages

• Reliable Mechanical Actuation
  • Utilizes a piston-spring mechanism. When fluid flow reaches the set point, it drives the piston, which magnetically couples to actuate a reed switch, outputting a switch signal. This passive mechanical structure offers strong interference resistance and high reliability.
• Adjustable Set Point
  • The flow set point can be flexibly adjusted via a knob or screwdriver according to actual requirements, adapting to the flow monitoring needs of different operating conditions.
• Safe Passive Contact Output
  • Provides SPDT (Single Pole, Double Throw) mechanical contacts (passive dry contact). Can directly drive alarms, indicators, or connect to PLCs, offering strong compatibility and simple wiring.
• Broad Media Compatibility
  • The valve body is available in materials like brass or stainless steel, with seals like NBR/FKM. Suitable for various media including water, oil, and air, with good corrosion resistance.
• Clear Indication & Compact Design
  • Some models feature a flow sight glass or operation indicator for easy on-site observation. Compact structure allows for convenient installation, suitable for piping with limited space.

Typical Application Scenarios

• Equipment Protection:​ Monitors coolant or lubricant flow; automatically alarms or shuts down equipment upon insufficient flow to prevent overheating or wear.
• Pump Control:​ Detects pump operational status to prevent dry running, such as providing low-flow protection.
• Process Control:​ Triggers subsequent equipment actions based on flow signals, like initiating backwash cycles in filtration systems.
• Energy Management:​ Monitors chilled water flow in central air conditioning systems for coordinated system operation.

Technical Parameters (Typical Values)

• Port Size:​ G1/2″ (The ’12’ may indicate the port size)
• Flow Setting Range:​ e.g., 3~30 L/min (for water, confirm based on specific model)
• Contact Rating:​ 5A/250VAC
• Pressure Rating:​ 1.0 MPa or higher
• Operating Temperature:​ -10℃ ~ +80℃ (Media Temperature)

SummaryThe PF3W521-12-2 flow switch acts as a “Sentry for Safety” in fluid systems. Through reliable mechanical detection and switch signal output, it provides a simple yet effective barrier of flow protection for equipment, effectively preventing malfunctions and production losses caused by flow abnormalities.Choosing the PF3W521-12-2 means selecting an economical, reliable, and straightforward flow monitoring solution!