GreenPrima PM820 2CL Residual Chlorine and Chlorine Dioxide Analyzer

Overview

The GreenPrima PM820 2CL is an online amperometric analyzer engineered for continuous, real-time monitoring of residual oxidants in water distribution and treatment systems. It operates on the constant-voltage amperometric principle—applying a fixed potential across a dual-platinum or gold working electrode assembly to selectively detect electroactive species including free chlorine (HOCl/OCl⁻), combined chlorine (chloramines), chlorine dioxide (ClO₂), and ozone (O₃). Unlike colorimetric or DPD-based methods, this technique eliminates reagent consumption, membrane replacement, and sample pretreatment, delivering stable, drift-free measurements under variable flow and temperature conditions. The integrated BAF615 constant-flow cell ensures laminar, pressure-independent sample delivery to the sensor surface—critical for reproducible current response and long-term calibration stability. Designed for regulatory compliance in municipal and industrial applications, the PM820 2CL meets functional requirements aligned with ISO 7888, ASTM D1253, and US EPA Method 334.1 for residual disinfectant monitoring.

Key Features

• Triple-oxidant capability: Simultaneous or selectable measurement of free chlorine, chlorine dioxide, and ozone without hardware modification
• Reagent-free, membrane-free operation: Eliminates consumables, reduces maintenance intervals, and avoids cross-contamination risks
• Dual-platinum or gold electrode configurations (Bsens650/Bsens660): Optimized for specific oxidant selectivity and interference rejection in complex matrices
• BAF615 precision flow cell: Maintains consistent 200–500 mL/min flow rate independent of upstream pressure fluctuations
• Full-temperature compensation: Supports NTC10K or PT1000 probes with automatic or manual compensation across -10 to 130 °C
• Robust data integrity architecture: Local storage of 600,000 timestamped readings with cyclic overwrite protection
• Configurable alarm logic: Two independent high/low setpoints with adjustable hysteresis and relay-rated output (5 A @ 250 VAC)
• Multi-mode installation: Field-adaptable for wall-mount, panel-mount, or direct inline pipe integration (IP65-rated enclosure)
• Secure operational interface: Password-protected configuration access, audit-trail-capable parameter logging, and firmware update via USB

Sample Compatibility & Compliance

The PM820 2CL is validated for use in potable water, hospital wastewater effluent, secondary distribution networks, cooling tower make-up, and pharmaceutical process water systems. Its amperometric detection scheme exhibits minimal interference from common ions (e.g., nitrate, sulfate, chloride ≤ 5,000 mg/L) and organic matter (up to 5 mg/L TOC), provided turbidity remains below 5 NTU. Sensor performance adheres to GLP-aligned calibration traceability protocols; factory calibration certificates include uncertainty budgets referenced to NIST-traceable chlorine standards. The analyzer supports FDA 21 CFR Part 11-compliant data export when paired with GreenPrima’s optional SecureLog software—enabling electronic signatures, user role management, and immutable audit trails required for GMP-regulated environments.

Software & Data Management

Configuration, diagnostics, and historical review are managed through the embedded web server (HTTP/HTTPS) or GreenPrima’s PC-based ConfigStudio v4.2. All communication interfaces—dual 4–20 mA analog outputs, RS485 Modbus RTU (slave ID configurable), and optional Ethernet/WiFi module—support seamless integration into SCADA, DCS, or cloud-based IIoT platforms. Data export formats include CSV and XML, with time-synchronized metadata (sensor ID, calibration date, temperature, flow status). Firmware updates preserve user-defined parameters and calibration coefficients. Remote diagnostics include electrode impedance monitoring, flow cell blockage alerts, and signal-to-noise ratio trending—enabling predictive maintenance scheduling based on sensor health metrics rather than fixed calendar intervals.

Applications

• Municipal drinking water treatment: Real-time verification of disinfectant residual at entry points, booster stations, and point-of-use locations
• Hospital central sterile supply departments (CSSD): Monitoring chlorine dioxide concentration in instrument sterilization loops per ISO 15883-5
• Pharmaceutical water systems: Continuous surveillance of ozone residuals in purified water (PW) and water-for-injection (WFI) distribution loops
• Food & beverage processing: Verification of chlorine levels in CIP rinse cycles and final product contact water
• Swimming pool and aquatic facility management: Automated dosing control feedback for chlorine and ozone generators
• Industrial boiler feedwater: Detection of residual oxidants that may accelerate corrosion in low-conductivity steam systems

FAQ

What electrode materials are supported, and how do they differ in application?
The PM820 2CL accepts either the Bsens650 (dual-platinum) or Bsens660 (gold) sensor. Platinum electrodes provide optimal sensitivity for free chlorine and chloramines in low-TDS potable water. Gold electrodes offer superior selectivity for chlorine dioxide in high-chloride environments such as seawater-influenced desalination effluents or brine recycling streams.

Is temperature compensation mandatory, and what probe types are compatible?
Yes—temperature compensation is integral to measurement accuracy due to the strong thermal dependence of electrode kinetics. The unit accepts either NTC10K thermistors or PT1000 RTDs; both are auto-detected and configured during setup.

Can the analyzer be used in pressurized pipeline applications?
Yes. When installed with the BAF615 flow cell and appropriate pressure-rated fittings (up to 10 bar), the system maintains stable operation in pressurized distribution mains without external pressure regulation.

How often does calibration verification require field intervention?
Under typical municipal water conditions, quarterly verification against a certified DPD comparator is recommended. Electrode zero checks can be performed daily using deionized water; slope verification requires a traceable standard solution (e.g., 2.00 ppm Cl₂ certified reference material).

Does the device support hazardous area classification?
The base unit is rated for general-purpose indoor use (IP65). For Zone 1/21 classified environments, GreenPrima offers an ATEX/IECEx-certified version (PM820 2CL-ATEX) with intrinsically safe sensor interface and explosion-proof enclosure options.