HACH American Sigma 900 Series Automatic Water Samplers

Overview

The HACH American Sigma 900 Series represents a purpose-built family of programmable automatic water samplers engineered for regulatory compliance, long-term unattended operation, and integration into comprehensive online water quality monitoring systems. Designed according to the fundamental principles of timed, flow-proportional, and event-triggered sampling—per ASTM D3370, ISO 5667-10, and EPA Method 1664—the 900 and 900MAX platforms operate on positive-displacement peristaltic pumping technology to ensure consistent sample integrity, minimal carryover, and precise volumetric delivery across variable head pressures and fluid viscosities. Unlike generic sampling peripherals, the 900 Series is architected as a system-level component: its controller firmware, sensor interface architecture, and mechanical sampling train are co-developed to support real-time synchronization with external flow meters, level sensors, rain gauges, or SCADA networks—enabling robust implementation of composite, discrete, and triggered sampling strategies in wastewater treatment plants, combined sewer overflows (CSOs), stormwater outfalls, and environmental research stations.

Key Features

• Precision Sampling Control: Dual-mode programming supports both time-based intervals (e.g., every 15 min, hourly, daily) and flow-proportional sampling (via analog 4–20 mA or pulse input from magnetic or ultrasonic flowmeters), with configurable volume per aliquot (10 mL to 2 L).
• Modular Hardware Architecture: Three physical configurations available—Portable (battery-operated, field-deployable), Refrigerated (4 °C ±2 °C active cooling with temperature logging), and All-Weather (NEMA 4X-rated enclosure, -20 °C to 50 °C operational range, integrated condensation management).
• Controller Flexibility: The 900 controller provides basic scheduling logic; the 900MAX adds advanced event logic—including multi-condition triggers (e.g., “sample if flow > 0.5 m³/s AND rainfall > 5 mm/hr”), alarm escalation via relay outputs, and onboard data buffering for up to 30 days of sampling events.
• Mechanical Reliability: Stainless-steel pump housing, chemically resistant tubing (Pharmed® BPT or Viton® options), and self-diagnostic motor current monitoring reduce unscheduled downtime and support predictive maintenance planning.
• Regulatory Readiness: Firmware supports audit-trail logging (date/time stamp, operator ID, sampling mode, volume, trigger condition), compliant with GLP and GMP documentation requirements under 21 CFR Part 11 when paired with validated HACH data management software.

Sample Compatibility & Compliance

The American Sigma 900 Series accommodates aqueous samples within pH 2–12 and suspended solids concentrations up to 10,000 mg/L, including raw sewage, treated effluent, surface runoff, and groundwater. Tubing material selection (standard silicone, Pharmed BPT, or Viton) ensures compatibility with chlorinated, acidic, or hydrocarbon-laden matrices. All models meet UL 61010-1 and IEC 61326-1 for electromagnetic compatibility and electrical safety. System validation protocols align with EPA Guidance for Quality Assurance Project Plans (QAPP) and ISO/IEC 17025 calibration traceability requirements when used with certified volumetric verification kits.

Software & Data Management

Configuration, diagnostics, and historical review are managed via SigmaLink™ PC software (Windows-compatible), which enables secure password-protected access, firmware updates, and export of CSV-formatted sampling logs with UTC timestamps. For enterprise deployment, the 900MAX supports Modbus RTU/TCP and OPC UA protocols—allowing seamless integration into plant-wide Historian systems (e.g., OSIsoft PI, Ignition SCADA) and automated report generation for NPDES permit submissions. Data integrity safeguards include cyclic redundancy check (CRC) on all serial communications and write-protected internal flash memory.

Applications

• Compliance monitoring at wastewater treatment plant influent/effluent points per NPDES permits
• Combined sewer overflow (CSO) event characterization and reporting
• Stormwater quality assessment at municipal outfalls (MS4 programs)
• Long-term ambient water quality trend analysis in rivers, lakes, and estuaries
• Biological monitoring campaigns requiring temperature-controlled preservation
• Industrial pretreatment program verification and industrial discharge tracking

FAQ

What distinguishes the 900 from the 900MAX controller?
The 900 supports basic time- and flow-triggered sampling. The 900MAX adds multi-parameter conditional logic, relay-based alarm actions, onboard event buffering, and enhanced communication protocol support.
Can the sampler be powered by solar or battery for remote deployments?
Yes—portable and all-weather models accept 12 V DC input and include low-voltage cutoff protection; optional solar charge controllers and deep-cycle battery kits are available through HACH-certified partners.
Is calibration required, and how is it verified?
While no routine calibration is mandated, volumetric accuracy is verified using NIST-traceable syringes or gravimetric methods per ASTM D3370 Annex A1; HACH provides documented procedures and verification templates.
Does the system support remote firmware updates or diagnostics?
Firmware updates require local USB connection; however, diagnostic status (pump revolutions, tube wear index, temperature history) can be polled remotely via Modbus or SigmaLink™ telemetry.
Are replacement parts and service support available globally?
Yes—HACH maintains authorized service centers in North America, EMEA, and APAC regions; critical spares (tubing, pump heads, batteries) are stocked with <72-hour lead time under standard distribution agreements.