Flowmax 42i EX Ultrasonic Flowmeter

Measuring liquid flow in hazardous environments requires both precision and certified safety. The Flowmax 42i EX is an explosion-proof ultrasonic flowmeter engineered for reliable, non-contact volumetric measurement of conductive and non-conductive liquids. Designed for chemical and industrial applications, it combines high measurement accuracy with ATEX and IECEx approval.

Ultrasonic Flowmeter for Hazardous Areas

The Flowmax 42i EX operates using ultrasonic transit-time technology, eliminating moving components and mechanical wear. Its smooth, slipstream-free channel geometry ensures hygienic operation and stable performance even when measuring aggressive or sensitive media.

Discover additional models within our ultrasonic flowmeter portfolio.

Key Features

• Non-contact ultrasonic measuring principle
• No moving parts – maintenance-free operation
• PP housing for high chemical resistance
• Integrated empty pipe monitoring
• Millisecond response time
• Optional PID control function
• Integrated control output for pumps or valves
• Preset quantity counter as standard

Technical Specifications

Mechanical Design

• Housing material: PP
• Available nominal diameters: DN3 / DN5 / DN7 / DN10 / DN15
• Measurement ranges: 0.012–60 l/min depending on size
• Protection class: IP65
• Medium temperature: 0 … 50 °C
• Nominal pressure: PN10

Electrical Data

• Power supply: 24 VDC, approx. 3.6 W
• Electrical connection: 8-pin plug or 8-core cable

Inputs and Outputs

• 1 digital input (e.g. dosing start)
• 2 digital outputs configurable as pulse or alarm
• 1 analogue output configurable as 0/4–20 mA
• RS-485 communication interface

Measurement Performance

• Accuracy: ±2% of reading or ±0.3% of full scale
• Optional calibration: ±1% of reading
• Repeatability: ≤ 0.5%
• Reference standard: VDI/VDE 2642

Explosion Protection Certification

Zone 1

• IECEx Ex mb IIC T6 Gb
• ATEX II 2G Ex mb IIC T6 Gb

Zone 2

• ATEX II 3G Ex mc IIC T6 Gc

Typical Applications

The Flowmax 42i EX ultrasonic flowmeter is suitable for:

• Chemical and petrochemical plants
• Solvent and aggressive media measurement
• Hazardous process environments
• Dosing systems and batch processes
• Systems with piston, diaphragm or peristaltic pumps

Why RST Elektronik

RST Elektronik delivers certified industrial measurement solutions tailored to demanding process requirements. Our ultrasonic flowmeter range supports both standard and explosion-proof installations with long-term reliability.

Request Technical Information

Contact our engineering team for detailed specifications, application guidance or pricing information for the Flowmax 42i EX ultrasonic flowmeter.