Thermal Flow Switch Technical Specifications

The principle structure is based on the thermal principle, which includes two resistors inside a sealed probe. One heated resistor serves as the detection resistor, and the other unheated resistor serves as the reference resistor. When the medium flows, the heat on the heating resistor is carried away, and the resistance value is changed.

The difference between the two resistors is used as the basis for judging the flow rate. 

No moving parts, maintenance free, easy to install, one model suitable for various pipe diameter requirements, continuously adjustable switch quantity, extremely low pressure loss, compact structure, color crystal display of flow trend and switch status, integrated temperature measurement function, supporting temperature alarm and remote measurement.

Principle Features

• 2 groups of 4-20mA analog signal output;
• Supports digital output, RS485 customizable
• Can monitor gas and liquid
• Not affected by pipeline static pressure
• Simple structure, no moving parts
• Easy installation, no need for on-site calibration and debugging, maintenance-free

Product Applications

• Cooling water, recirculating water, critical water flow monitoring
• Organic and inorganic solution flow monitoring
• Gas (oxygen, nitrogen, ammonia, natural gas, etc.) flow monitoring
• Anti-freeze protection, spraying systems, sewage protection, etc.
• Strong anti-contamination ability

Technical Parameters

Flow Range: 0.01…2.0m/s (water) ◇ Response Time: 1…13s, typical value 2s
Temperature Range: 0…100℃ ◇ Initialization Time: <16s
Temperature Accuracy: ±1.5℃ when the probe is immersed in the medium ◇ Electrical Protection: Reverse polarity, short circuit, overload protection
Signal Output: Temperature (PNP/NPN/IO-link, analog 0/4…20mA, 0/1-5/10V) ◇ Protection Class: IP67
Flow (PNP/NPN/IO-link, analog 0/4…20mA, 0/1-5/10V)
Medium Temperature: -20…100℃ (NK210 series)
Power Supply: 24V±20%DC ◇ Ambient Temperature: -20…80℃
Max Operating Current: Max 200mA (PNP or NPN type) ◇ Storage Temperature: -20…80℃
Current Consumption: <100mA ◇ Connection Method: M12 connector
Flow Display: Color LCD display (0.96 inch) ◇ Material:
Temperature Display: Color LCD display (0.96 inch)
Table Head: Stainless Steel/Engineering Plastic
Setting Method: Button Setting
Shell: Stainless Steel
Pressure Resistance: 100bar ◇ Contact Material:
Temperature Gradient: ≤4°C/S
Stainless Steel 316L/EPDM (Ethylene Propylene Diene Monomer)

Model Selection Table