ifm efector SI Series Flow Switch

Provides reliable monitoring of liquids and gases with up to 100cm/s flow rate in 1/8 to 8in pipes using thermal flow sensing technology.

ifm efector SI Series Flow Switch (Model SI5006)
ifm efector SI Series Flow Switch (Model SI500A)
ifm efector SI Series Flow Switch (Model SI5000)
ifm efector SI Series Flow Switch (Model SI5001)
ifm efector SI Series Flow Switch (SI5002, 5003, 5007, 5010-12, 5100, 0521, 0550, 0553, 0558)
ifm efector SI Series Flow Switch (Model SI6000)
ifm efector SI Series Flow Switch (Model SI6100)
ifm efector SI Series Flow Switch (Model SI6200)
ifm efector SI Series Flow Switch (Model SI6700)
ifm efector SI Series Flow Switch (Model SI6800)

Starting at $489.00

Effective August 12th, 2025, ifm effector has added a 12% surcharge to this product. The surcharge will appear as a separate line item on the order.

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By ifm efector

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Product Manual Product Specs (22 Files)

Features

3 to 100cm/s flow rate
-25 to 95°C temperature ranges
30 to 300bar pressure rating
~ ±10% accuracy
High repeatability
45 to 55mm probe lengths
7.7 or 8.2mm probe diameter
For 1/8 to 8in line sizes
Process connections:
- M18 x 1.5 internal thread
- Aseptoflex external thread
- G1 external thread Aseptoflex Vario
Output options:
- 1 or 2 digital outputs
- 1 analog output
Digital output details:
- Digital switching signal
- PNP, NPN, or Relay electrical design
- Optional IO-Link
- Normally open/closed function (configurable)
Analog output details:
- Analog output signal
- 4-20mA analog current output
- Model with this output is only compatible with liquid media
M12 (coding A) or 1/2in (coding C) electrical connection
- Gold-plated contacts for hygienic models
Setting values can be electronically locked
Additional process connection adapters available separately

The ifm efector SI Series Flow Switch utilizes thermal flow sensing technology to monitor the flow of liquids and gases within pipes of industrial and hygienic applications. The SI series offers a flow velocity range of 3 to 100 cm/s across line sizes from 1/8 to 8 inches, with the capability to withstand medium temperatures from -13 to 176°F (-25 to 80°C) and pressures up to 4350 psi. Models designed for sanitary applications can withstand temperatures up to 95°C and SIP processes up to 140°C.

The SI series features a robust stainless steel housing, which provides high reliability in harsh operating conditions. It also features a simple, user-friendly setup. Once installed, the flow range and switch points are adjusted with the push-button display on the unit. The multicolor LED display of the SI flow switch indicates the nominal flow range and the switch point. For added security, the SI series includes electronic locking capabilities to prevent accidental setting adjustments and offers an option to restore the unit to the factory settings if needed.

The thermal flow sensing technology of the SI series relies on the cooling effect of flowing liquids. A higher flow velocity results in a greater cooling effect, and this can be reliably measured. The sensor tip houses two platinum RTD elements and a heat source. When power is applied, the sensor tip is heated. The difference in temperature between the two RTDs is then held constant by varying the amount of power applied to the heater. The flow rate is determined as these RTDs react to the physical effect of a flowing medium, conducting heat energy away from the sensor tip. This temperature-based operating principle can reliably sense the flow of virtually any liquid or gas.

Some models are available with IO-Link capabilities. With IO-Link, the SI series can provide information, including the current flow velocity up to 140% of the taught flow rate, the current medium temperature, and the status of switching signals. Instantaneous data delivery on flow velocity enables precise, real-time control over fluid dynamics, optimizing system efficiency and responsiveness to changing conditions. Real-time communication of flow presence or absence also safeguards pumps against dry running, reducing the risk of costly repairs or replacements. When the SI series is used in cooling water management, IO-Link provides temperature monitoring to ensure that critical components receive adequate cooling, preventing overheating and associated downtime or damage.