GreenPrima PROL EV200 Ultrasonic Level Transmitter

Overview

The GreenPrima PROL EV200 Ultrasonic Level Transmitter is a high-performance, microprocessor-based level measurement instrument engineered for reliable non-contact distance determination using the time-of-flight (ToF) principle. It emits a short ultrasonic pulse from a piezoelectric transducer mounted on the top of a vessel or silo; the pulse reflects off the surface of the material (liquid or solid) and returns to the sensor. The elapsed time between transmission and echo reception—corrected for ambient temperature via an integrated Pt1000 sensor—is converted into a precise distance value, which is then scaled to engineering units (e.g., % full, meters, or feet). Designed for continuous operation in demanding industrial environments, the PROL EV200 delivers stable performance across variable dielectric constants, low-reflectivity surfaces, dust-laden atmospheres, and fluctuating vapor conditions—without requiring physical contact with the medium.

Key Features

• Intelligent adaptive signal processing with automatic gain control (AGC) and real-time power adjustment to maintain optimal signal-to-noise ratio across changing process conditions.
• Digital temperature compensation using a calibrated Pt1000 sensor ensures consistent acoustic velocity correction across the full operating range (−30 to +70 °C).
• Advanced echo profiling algorithm with dynamic interference suppression filters out false echoes from internal structures (e.g., agitators, ladders, feed chutes) and reverberation artifacts.
• High-resolution waveform analysis engine improves detection reliability for low-amplitude returns typical of foam, granular solids, or highly viscous liquids.
• Robust housing constructed from UV-stabilized polycarbonate (PC) and polypropylene (PP), rated IP67 for outdoor and washdown environments.
• ATEX-certified intrinsic safety (Ex ia II C T6) enables safe deployment in Zone 0/1 hazardous areas without additional barriers.
• G2″ BSP process connection provides mechanical stability and sealing integrity under static pressures up to 1.5 bar.

Sample Compatibility & Compliance

The PROL EV200 is compatible with a broad spectrum of process media—including potable water, wastewater, acids, alkalis, slurries, grains, pellets, and powdered polymers—provided the material exhibits sufficient acoustic reflectivity. Its ETFE or PVDF sensor diaphragm resists chemical attack from aggressive media such as chlorine solutions, sodium hypochlorite, sulfuric acid (≤50%), and caustic soda (≤30%). The device complies with IEC 61000-6-2 (immunity) and IEC 61000-6-4 (emissions), meets EMC Directive 2014/30/EU, and carries UKCA and CE marking. For regulated industries, its firmware supports audit-trail-enabled configuration logging and adheres to foundational requirements of IEC 62443-3-3 for secure device management.

Software & Data Management

Configuration and diagnostics are performed locally via the integrated backlit LCD interface or remotely via HART-compatible handheld communicators (e.g., Rosemount 375/475). The transmitter supports standard 4–20 mA analog output with optional linearization, damping, and fail-safe behavior (e.g., upscale/downscale on signal loss). While the base model does not include Modbus RTU or relay outputs (available on the PROL EV300 variant), its analog loop is fully compatible with DCS, PLC, and SCADA systems compliant with ISA-50.00.01 (analog signaling standards). All calibration parameters, diagnostic events (e.g., “low signal strength”, “temperature out of range”), and firmware version metadata are retained in non-volatile memory for traceability during GLP/GMP audits.

Applications

The PROL EV200 is routinely deployed in municipal water and wastewater infrastructure (e.g., influent wells, equalization basins, filter backwash tanks), food & beverage production (sugar syrup tanks, dairy silos, CIP solution vessels), chemical manufacturing (acid storage, catalyst hoppers), and mineral processing (fly ash bunkers, limestone feed hoppers). Its immunity to conductivity, density, and viscosity variations makes it especially suitable where radar alternatives face challenges—such as low-dielectric hydrocarbons or dusty cement applications. Field validation per ISO 11787 confirms repeatability better than ±1 mm under steady-state conditions across its 10 m range.

FAQ

What is the minimum measurable distance (blind zone) for the PROL EV200?
The blind zone is 0.5 m—this is the near-field region immediately below the transducer where echoes cannot be reliably distinguished from the initial pulse ring-down.
Can the PROL EV200 measure level in pressurized vessels?
Yes, it is rated for continuous operation at up to 1.5 bar gauge pressure when correctly installed with a G2″ threaded seal and appropriate gasket material (e.g., EPDM or Viton).
Is temperature compensation automatic and factory-calibrated?
Yes—the integrated Pt1000 sensor continuously measures ambient transducer temperature, and the microprocessor applies a pre-characterized acoustic velocity curve for dry air, eliminating manual offset adjustments.
How does the device handle foam or vapor layers above the liquid surface?
It employs multi-echo discrimination logic to prioritize the strongest, most consistent return—typically the true liquid surface—while rejecting attenuated or dispersed reflections from foam or condensate.
Does the PROL EV200 support SIL certification for safety instrumented functions?
No—the device is not certified to IEC 61508 or IEC 61511 for use in Safety Integrity Level (SIL) loops; it is intended for general-purpose process monitoring only.