The thermal flow switch is primarily used for online or insertion installation in pipelines carrying water, gases, or oils to monitor the flow rate of water in a system. When the flow rate exceeds or falls below a certain setpoint, it triggers an alarm signal to the system. The system then responds accordingly to prevent or reduce the risk of "dry running" of the main unit.
Based on the thermal principle, the thermal flow switch contains two resistors within a sealed probe. One resistor is heated to act as the detection resistor, while the other remains unheated as the reference resistor. When the medium flows, the heat received by the thermal sensor changes with the flow rate. The thermal sensor converts this temperature difference into an electrical signal. When the flow rate reaches a setpoint, the thermal flow switch outputs a switch signal.
Product Features
Minimal pressure loss: Ensures efficient flow monitoring with almost no impact on system pressure.
Multiple material options: Available in multiple materials to suit different media and environments.
Complete insulation: The mechanical and electronic components are completely insulated, making it ideal for low-flow applications with cost-effective performance.
High-precision settings: Features an adjustable on/off scale, eliminating the need for on-site user adjustments.
Status LED indicator: Provides a clear visual indication of switching status with dual switching outputs for enhanced functionality.
Instrument Parameters
Accuracy: ±5% of total volume
Hysteresis: Minimum 0.5 L/min, depending on switching point
Switching configuration scale:
Calibrated in horizontal installation using water at 20°C.
Switching values may vary slightly due to mounting position, medium, and temperature.
LED Screen:
Models with direct current (DC) power supply have an LED display for the switching state.
Models with AC power supply do not include LED display.
Wiring method: Connectors, Hirschmann connectors, direct output
Output: Reed switch, 24VDC/250VAC capacity, 100mA
Materials:
Cell: Silicone
Piston: Plastic POM
Type: Stainless Steel
Pressure resistance:
50 bar (aluminum type)
100 bar (stainless steel type)
Average pressure loss: 0.3 bar at 25 L/min
Medium Temperature: Maximum 90°C
Protection class: IP65
Note: The mounting position affects the switching values.
