HACH Orbisphere 3658 Dissolved Oxygen and Gas Analyzer

Overview

The HACH Orbisphere 3658 is an advanced, continuous online analyzer engineered for high-precision measurement of dissolved oxygen (DO) and multiple process gases—including O₂, CO₂, N₂, CH₄, and H₂S—in liquid and gas phases across municipal and industrial water, wastewater, biogas, and fermentation applications. Utilizing electrochemical sensing technology with temperature-compensated amperometric detection, the system delivers stable, drift-free performance under variable flow, pressure, and temperature conditions. Its modular architecture integrates a rugged field-mounted analyzer unit with interchangeable sensor modules—enabling flexible configuration for single-gas or multi-parameter monitoring without hardware replacement. Designed for 24/7 operation in demanding environments, the Orbisphere 3658 meets the functional safety requirements of IEC 61508 SIL 2 and supports critical process control loops in activated sludge basins, anaerobic digesters, and membrane bioreactors (MBRs).

Key Features

• Multi-gas capability via plug-and-play sensor modules—each calibrated and validated independently per ISO 17025-accredited procedures
• Patented low-maintenance galvanic DO sensor with extended service life (>12 months) and automatic zero/span verification cycles
• Integrated temperature, pressure, and conductivity compensation algorithms compliant with ISO 5814 and ASTM D888 standards
• Real-time diagnostics including sensor health monitoring, electrolyte level detection, and membrane integrity alerts
• Configurable analog and digital outputs supporting seamless integration into DCS, SCADA, and PLC systems (Modbus RTU/ASCII, EtherNet/IP, PROFIBUS DP)
• ATEX-certified variants available for Zone 1/21 hazardous area installations (II 2G Ex db IIB T4 Gb / II 2D Ex tb IIIB T135°C Db)

Sample Compatibility & Compliance

The Orbisphere 3658 accommodates a broad range of aqueous matrices—including raw sewage, activated sludge, treated effluent, potable water, and biogas condensate—with minimal fouling risk due to its self-cleaning flow cell design and optional ultrasonic anti-fouling module. Sensor housings are constructed from 316L stainless steel and PTFE-lined wetted parts to resist corrosion from chlorinated, sulfidic, or acidic media. The analyzer conforms to key regulatory and quality frameworks: EN 14181 (QAL1/QAL2), US EPA Method 365.2 for DO, ISO 9001-certified manufacturing, and full traceability to NIST-traceable calibration standards. Data integrity is ensured through built-in audit trails meeting FDA 21 CFR Part 11 requirements when operated with HACH’s AquaSuite™ software.

Software & Data Management

HACH AquaSuite™ software provides centralized configuration, remote calibration, trend analysis, and alarm management for fleets of Orbisphere 3658 analyzers. It supports automated report generation aligned with ISO/IEC 17025 documentation requirements and exports time-stamped data in CSV, PDF, and XML formats. Secure web-based access enables role-based user permissions, encrypted data transmission (TLS 1.2+), and integration with enterprise asset management (EAM) platforms via RESTful APIs. Firmware updates are delivered over-the-air (OTA) with version-controlled rollback capability and change-log documentation for GLP/GMP validation purposes.

Applications

• Real-time DO optimization in aerobic biological treatment processes to reduce energy consumption by up to 25% in blower control strategies
• Biogas composition monitoring (CH₄/CO₂/H₂S) for digester health assessment and renewable energy yield forecasting
• Deaerator and boiler feedwater monitoring to prevent oxidative corrosion in power generation facilities
• Process water quality assurance in pharmaceutical manufacturing per USP and EU GMP Annex 1 guidelines
• Regulatory compliance reporting for NPDES permits and ISO 14001 environmental management systems

FAQ

What sensor technologies does the Orbisphere 3658 support?
It employs galvanic (for DO) and electrochemical (for CO₂, H₂S, O₂) sensing principles; infrared (IR) and thermal conductivity (TC) modules are available as factory-installed options for CH₄ and N₂.
Can the analyzer operate in sub-zero ambient temperatures?
Yes—standard units are rated for −20 °C to +50 °C ambient; heated enclosures and trace-heated sample lines are available for sustained operation down to −40 °C.
Is third-party calibration verification supported?
Yes—the system provides standardized calibration port interfaces and documented uncertainty budgets compatible with independent ISO/IEC 17025 laboratories.
How frequently is maintenance required?
Sensor replacement intervals range from 6–18 months depending on matrix severity; routine verification (zero/span checks) is programmable from daily to weekly intervals.
Does it meet cybersecurity standards for industrial control systems?
Yes—it complies with IEC 62443-3-3 SL2 requirements, featuring secure boot, firmware signature validation, and configurable firewall rules via embedded Linux OS.