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Reduce mechanical failure points
No paddle, rotor or flap is required in the measurement principle.
ifm · Flow sensing
ifm SA Thermal Flow Sensors
Monitor flow and medium temperature with insertion-style calorimetric sensors for water, oil, glycol and air. SA is strongest for flow/no-flow, cooling and pump-protection applications where a compact electronic sensor is preferred over mechanical flow switches.
CalorimetricFlow + temperatureIO-LinkRelative / absolute modesNo moving parts
Line sizes½"…16"Family application envelope
Probe options19…200 mmRepresentative current selection
MediaLiquid / gasApplication and mode dependent
Process valuesFlow + temperatureVia outputs / IO-Link by model
Thermal flow monitoring
An electronic alternative to paddle wheels and mechanical flow switches
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Flow and temperature
Current SA routes can report flow and medium temperature through one device.
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Insertion-style probes
Longer probe variants support larger pipes when installation depth is engineered correctly.
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Digital process transparency
Access current flow velocity, temperature, device status and additional parameters through IO-Link.
Applications
Protect pumps and confirm cooling-media flow
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Run-dry detection
Simple flow/no-flow switching can protect pumps from operation without adequate medium.
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Water / glycol flow
Monitor cooling flow and temperature to help prevent overheating and quality problems.
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Insertion measurement
SA4 long-probe versions can be inserted into larger pipe diameters when straight runs and insertion depth are correct.
Calorimetric principle
Flow is inferred from how quickly the moving medium carries heat away
The SA tip contains two platinum RTDs and a heat source. One element responds to heat removed by the flowing medium while the reference element tracks medium temperature. The electronics vary heater power to maintain a defined temperature difference; the required power changes with flow.
Relative modeTeach low and high flow for a 0–100% reference; useful for many media.
Absolute modeConfigured for defined media and pipe geometry; best suited to supported media and larger pipes.
Temperature influenceRapid medium-temperature changes can affect thermal flow measurement.
Build-upDeposits on the sensor tip can change heat transfer and therefore measurement behaviour.
IO-Link
One digital connection for flow, temperature and device status
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Current process value
Read current flow velocity digitally without analogue conversion losses.
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Second process value
Retrieve medium temperature together with flow.
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Device diagnostics
Read current device state and switching information.
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Commissioning data
Access maximum flow and current flow-rate parameters depending on configuration.
Representative SA models
Select by probe length, process connection and output architecture
| Models | Probe | Process connection | Output route | Typical use |
|---|---|---|---|---|
| SA6010 / SA6014 | 27 mm | ½" NPT | Switching / frequency / 4–20 mA or dual analogue by variant | Compact threaded installation |
| SA5010 / SA5014 | 45 mm | M18 × 1.5, adapter required | Variant dependent | Flexible adapter-based installation |
| SA4110 / SA4114 | 100 mm | 8 mm probe + compression fitting | Variant dependent | Larger pipe insertion |
| SA4310 / SA4314 | 200 mm | 8 mm probe + compression fitting | Variant dependent | Deep insertion / large pipe |
| SA2000 / SA2004 | 19 mm | G ½ BSPP | Variant dependent | Compact metric process route |
Installation criteria
Thermal flow sensing depends strongly on the installation
Critical points
Correct insertion depth, pipe filling, sensor alignment and straight runs are essential if the SA is expected to provide stable repeatable flow information.
Straight runTypically 5–10 × pipe diameter upstream and 3–5 × downstream depending on disturbance
InsertionSensor tip must be within the flowing medium
Preferred mountingVertical pipe with upward flow where practical
Media changesRapid temperature changes can disturb thermal measurement
Build-upDeposits on the tip affect heat transfer
Compressed-air meteringUse SD when accurate consumption / totalising is the primary requirement
Requirement capture
Inputs required to select the SA sensor
MediumWater, glycol, oil, air or other flowable medium.
Pipe sizeInternal diameter and available insertion point.
Flow rangeMinimum, normal and maximum flow or velocity.
TemperatureNormal and worst-case medium temperature.
ConnectionNPT, BSPP, adapter or compression fitting.
OutputSwitching, frequency, 4–20 mA and/or IO-Link.