GreenPrima ProLev300 Intrinsically Safe Integrated Ultrasonic Level Transmitter

Overview

The GreenPrima ProLev300 is an intrinsically safe, integrated ultrasonic level transmitter engineered for continuous, non-contact measurement of liquid and solid material levels in hazardous and demanding industrial process environments. Based on the time-of-flight (ToF) principle, the device emits high-frequency ultrasonic pulses (typically 50–70 kHz) toward the surface of the medium and precisely calculates distance by measuring the elapsed time between pulse emission and echo return. This method eliminates mechanical wear, requires no physical contact with the process medium, and ensures long-term stability without calibration drift under consistent environmental conditions. Designed specifically for Zone 0/1 and Division 1 classified areas, the ProLev300 complies fully with ATEX Directive 2014/34/EU for equipment intended for potentially explosive atmospheres containing gas groups IIC and temperature class T6. Its robust architecture supports operation across a wide ambient temperature range (−30 to +70 °C) and up to 1 bar overpressure — suitable for open tanks, silos, sumps, and chemical storage vessels where intrinsic safety is mandated by process safety management (PSM) protocols.

Key Features

• Intrinsically safe design certified to ATEX II 1/2G Ex ia IIC T6 Ga — approved for continuous operation in Zone 0, Zone 1, and Division 1 hazardous locations
• Integrated electronics and transducer housed in a single compact unit — simplifies installation, reduces cabling complexity, and minimizes failure points
• Dual-range configuration: selectable 0.25–5 m or 0.4–8 m measurement spans via DIP switch or software configuration
• High-resolution output: 1 mm distance resolution with ±0.2% full-scale accuracy — traceable to NIST-traceable reference standards
• Four-button local interface with intuitive menu navigation — enables zero/span adjustment, damping setting, relay logic programming, and diagnostics without external tools
• 4-wire architecture delivering simultaneous analog (4–20 mA), digital (Modbus RTU over RS-485), and discrete (2 × SPDT) outputs — supports layered control strategies and redundancy requirements
• IP68-rated housing constructed from anodized aluminum and chemically resistant PVDF — withstands washdown, corrosion, and outdoor exposure

Sample Compatibility & Compliance

The ProLev300 is validated for use with homogeneous liquids (e.g., water, acids, alkalis, solvents, wastewater) and free-flowing bulk solids (e.g., plastic granules, grain, limestone, coal). It performs reliably in applications where vapour layers, light surface foam, or moderate dust loading are present — though dense foam, heavy condensation, or turbulent agitated surfaces may require site-specific evaluation. The instrument meets electromagnetic compatibility (EMC) requirements per EN 61326-1:2013 and functional safety guidelines aligned with IEC 61508 SIL 2 (hardware fault tolerance). All firmware and configuration data are retained during power loss. Documentation includes EU Declaration of Conformity, ATEX Certificate of Conformity (issued by notified body), and compliance statements for RoHS, REACH, and WEEE directives.

Software & Data Management

Configuration and diagnostics are supported via GreenPrima’s PC-based LevConfig Suite (Windows), which connects via USB-to-RS485 adapter. The software provides real-time echo curve visualization, signal strength monitoring, automatic noise filtering threshold adjustment, and diagnostic logging compliant with FDA 21 CFR Part 11 requirements when used in regulated pharmaceutical or food manufacturing settings. Modbus RTU registers support read/write access to all operational parameters, including measured distance, temperature compensation value, relay status, and error codes (e.g., ‘No Echo’, ‘Signal Weak’, ‘Overrange’). Audit trails record configuration changes with timestamp, user ID, and parameter delta — essential for GLP/GMP validation and internal QA audits.

Applications

• Chemical processing: Level monitoring of flammable solvent tanks, acid neutralization sumps, and catalyst storage silos
• Pharmaceutical manufacturing: Non-invasive tank level verification in API synthesis and purified water distribution systems
• Water & wastewater: Sludge level detection in anaerobic digesters and grit chamber inventory control
• Food & beverage: Monitoring of sugar syrup, vegetable oil, and ethanol storage under hygienic and explosion-proof conditions
• Mining & aggregates: Silo level supervision for dry bulk materials in dusty, high-vibration environments

FAQ

Is the ProLev300 suitable for measuring level in pressurized vessels?
No — it is rated for maximum 1 bar gauge pressure and must be installed on atmospheric or vented vessels. For pressurized applications, consult the ProLev-HighPressure variant series.

Can the device operate in vacuum conditions?
Ultrasonic propagation requires a gaseous transmission medium; operation below ~50 mbar absolute pressure is not recommended due to insufficient acoustic coupling.

What is the minimum recommended distance between the transducer face and the highest expected material level?
The blind zone is 0.25 m (standard range) or 0.4 m (extended range); this clearance must be maintained to ensure reliable echo detection and avoid near-field interference.

Does the instrument support HART communication?
No — the ProLev300 uses Modbus RTU as its digital protocol. HART-capable models are available under the ProLev-HART product line.

How is temperature compensation handled?
An integrated Pt1000 sensor measures ambient transducer temperature and dynamically adjusts sound velocity in air using the ISO 9613-1 standard algorithm, ensuring consistent accuracy across the full operating temperature range.