Product Overview

The Integrated Thermal Flow Switch NK300-T Series is designed for reliable flow and temperature monitoring in industrial process systems. The sensor probe incorporates dual temperature sensors, with one sensor connected to a heat source and the other serving as a reference for temperature compensation.

During operation, changes in medium flow cause corresponding temperature changes, allowing the instrument to accurately detect flow conditions while compensating for process temperature variations. The NK300-T can function as either a flow sensor or a flow switch, providing highly stable and repeatable switching performance. With an adjustable measuring range of 300:1, it is capable of detecting ultra-low flow rates across a wide range of industrial applications.

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Why Choose the  Integrated Thermal Flow Switch NK300-T ?

The NK300-T Series combines flow measurement and temperature monitoring in one compact device, helping simplify system design while improving process reliability.

Key Advantages

• Simultaneous flow and temperature monitoring
• Dual temperature sensor design with temperature compensation
• No moving mechanical parts for reliable operation
• Suitable for liquids, gases, and slurry media
• Detects ultra-low flow with a wide adjustable range (300:1)
• Multiple output options for PLC and automation systems
• High pressure resistance up to 100 bar
• Compact design with threaded or flanged installation options
• High reliability with low maintenance requirements

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Working Principle

The NK300-T Series operates based on the thermal dispersion principle.

The sensing probe contains two temperature sensors:

• One sensor is positioned near the internal heat source.
• The second sensor is isolated from the heat source and serves as the reference sensor.

As the process medium flows past the probe, heat is transferred away from the heated sensor. The resulting temperature difference between the two sensors changes according to the flow velocity.

The controller continuously analyzes this temperature difference to determine the flow condition while simultaneously providing temperature compensation for improved measurement stability.

Depending on the application, the device can operate as a flow sensor, a flow switch, or provide both flow and temperature monitoring simultaneously.

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Product Features

• Dual temperature sensor technology
• Simultaneous flow and temperature monitoring
• No moving mechanical parts
• High repeatability and reliable switching performance
• Temperature measurement up to 100°C
• Pressure resistance up to 100 bar
• Suitable for low-flow measurement
• Threaded and flanged process connections available
• Optional extended probe design
• Cost-effective industrial solution
• Suitable for continuous industrial operation

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Product Applications

The NK300-T Series is suitable for monitoring liquids, gases, and slurry media in industrial process systems.

Common Applications

• Flow indication and monitoring
• Circulating cooling water systems
• Furnace cooling systems
• Oil tanker unloading
• Agitated tank liquid monitoring
• Safety diaphragm monitoring
• Safety valve flow control

Pump Protection Applications

• Pump low-flow protection
• Seal leakage detection
• Bearing lubrication monitoring
• Air pocket alarm
• Chemical dosing pump monitoring

Industrial Industries

• Water treatment
• Chemical processing
• Petrochemical
• Power generation
• Machinery manufacturing
• Hydraulic systems
• Lubrication systems
• Process automation

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Typical Application Example

Cooling Water Flow Monitoring in Industrial Equipment

Industrial cooling systems require continuous monitoring of flow conditions to prevent overheating and equipment failure.

The NK300-T Series can be installed directly on the cooling pipeline to monitor both flow rate and medium temperature simultaneously. When the flow falls below the preset threshold or abnormal temperature conditions occur, the controller sends switching or analog signals to the PLC, enabling timely alarms or equipment protection.

Because the sensor contains no moving mechanical parts, it provides stable long-term operation while reducing maintenance requirements.

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Technical Specifications

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Size Chart

 

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Wiring Diagram

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Frequently Asked Questions (FAQ)

What media can the NK300-T monitor?

The NK300-T is suitable for liquids, gases, and slurry media within the specified measuring ranges.

Can it monitor both flow and temperature?

Yes. The integrated design allows simultaneous flow monitoring and temperature detection using dual temperature sensors.

Does the sensor contain moving mechanical parts?

No. The NK300-T uses thermal dispersion technology and contains no moving parts, helping reduce maintenance requirements.

Which output options are available?

The device supports PNP, NPN, Relay (SPDT), and optional 4–20mA analog output, making it suitable for PLC and industrial automation systems.

Where is the NK300-T commonly used?

Typical applications include pump protection, cooling water monitoring, lubrication systems, chemical dosing, furnace cooling, and industrial process automation.