Is HNF40-C the right choice for your application?

Select this model when all of the following conditions are met:

• The medium is a low-flow liquid within 0.5–15 L/min (three range scales available).

• You need to monitor both flow and temperature in one sensor on the same line.

• Local LED indication of flow and temperature is needed for panel or maintenance viewing.

• Two configurable alarm contacts (NPN/PNP) are required for flow or temperature over-limit protection.

• The equipment piping is G1/2 or G3/8 female thread, supply is 24 VDC, and compact, cost-effective integration is desired.

• Scale/corrosion resistance, low pressure loss and good repeatability for continuous operation are required.

Please consult us first if: flow exceeds 15 L/min, medium temperature exceeds 100 °C, the liquid carries many hard solids, a corrosion-resistant wetted material (e.g. 316L) is required, or explosion-proof / higher ingress protection beyond the standard ABS housing is needed.

Why choose an integrated flow & temperature sensor

Flow + temperature in one sensor

Measures both flow and temperature in a single instrument, eliminating a separate temperature tap and second sensor and saving internal space and integration cost.

High accuracy, stable and repeatable

Flow accuracy up to class 0.5 (optional class 0.3), temperature resolution 0.1 °C. Scale-resistant, corrosion-resistant, low pressure loss, drift-free long-term performance – ideal for OEM equipment integration.

Dual alarms plus analogue output

Two configurable alarm contacts (NPN/PNP) for over-limit alarming and interlock protection, together with 4–20 mA and adjustable pulse outputs to PLC and data acquisition systems.

LED display, easy install and maintain

A 3-digit LED shows flow and temperature in real time. G1/2 and G3/8 threads screw directly into equipment piping on 24 VDC supply – simple construction and low installation cost.

Technical Specifications

Installation & Commissioning

Confirm 4 items before ordering:

1. Normal and maximum flow – to select the 0.5–5 / 1.5–10 / 5–15 L/min range scale.

2. Equipment pipe thread (G1/2 or G3/8) and medium temperature range.

3. Alarm contact type (NPN or PNP) and alarm setpoints (flow/temperature).

4. Whether 4–20 mA or pulse output is needed and the PLC-side interface requirements.

Align the flow direction with the body arrow and keep a short straight section before and after the sensor for stable impeller pickup. After wiring, set the flow and temperature alarm thresholds; power up and verify the LED reading against actual conditions, and confirm both alarm switching directions match the PLC logic before automatic operation.

Outputs & System Integration

• Two alarm contacts (NPN / PNP): independently configurable as flow or temperature alarms to trigger equipment interlock, warning light or shutdown protection.

• 4–20 mA analogue output: continuously transmits flow and temperature to PLC analogue modules or recorders for process monitoring and data acquisition.

• Pulse output (adjustable): frequency signal proportional to flow, scalable to the pulse equivalent required by totalisers or PLC high-speed counters.

• LED local display: 3-digit display shows flow and temperature in real time, eliminating the need for a separate indicator.

For OEM volume projects, please specify range scale, thread, NPN/PNP type, alarm setpoints and output method with your enquiry so we can match the optimal cost configuration.

Typical Applications

Semiconductor equipment cooling

Monitors cooling water flow and temperature on etching, grinding, slicer and CVD equipment, triggering immediate alarms to protect precision process chambers.

Machine tool & injection moulding coolant management

Monitors water-soluble coolant flow and temperature on machine tools, injection moulding and forging machines, preventing tool overheating or mould damage from insufficient cooling.

Photovoltaic & powder metallurgy equipment

Integrated into photovoltaic, powder metallurgy and high-end manufacturing equipment to monitor process cooling water flow and temperature for consistent process performance.

Food & pharmaceutical equipment

Used for conductivity testing and temperature monitoring of water/gas circulation in food and pharmaceutical equipment, meeting clean equipment integration requirements.

Battery factories & water treatment

Deployed as an equipment-level flow-temperature sensing element in battery factories, petrochemical, power, metallurgy & steel, papermaking, food processing and water treatment.

Information Required for Selection

To confirm the correct HNF40-C configuration, please provide: normal and maximum flow, pipe thread (G1/2 or G3/8), medium name & temperature, alarm contact type (NPN/PNP), alarm setpoints (flow/temperature), whether 4–20 mA or pulse output is required, and accuracy class (0.5 / 0.3). If necessary we will request additional details on mounting orientation and ambient temperature.

Frequently Asked Questions

What low-flow ranges are available?

Three range scales: 0.5–5 L/min, 1.5–10 L/min and 5–15 L/min, covering low-flow liquid measurement across 0.5–15 L/min.

Can the LED show flow and temperature?

Yes. The 3-digit LED displays liquid flow and temperature in real time for easy on-site and panel-side viewing.

Does it provide two configurable alarm contacts?

Yes. Two alarm contacts, NPN or PNP selectable, can be configured independently as flow or temperature alarms for over-limit interlock and protection.

How quickly can the switching output respond to a flow or temperature event?

Switching response is ON ≤ 2 s and OFF ≤ 2 s, typically 1–2 s, meeting real-time alarming requirements for most equipment cooling and temperature protection duties.

Which G1/2 or G3/8 connection fits the intended equipment piping?

Both threads are available – choose by your existing equipment port. G3/8 suits compact small-bore machines; G1/2 suits conventional equipment cooling water circuits.

Downloads

HNF40-C Flow Temperature Online Sensor Datasheet (PDF)

Insert the download link here after uploading the PDF to your website.