ATAGO CM-800α-SW In-Line Salinometer
| Brand | ATAGO |
|---|---|
| Origin | Japan |
| Model | CM-800α-SW |
| Measurement Range | 0.0–28.0% (ATC) |
| Accuracy | ±0.1% (salinity), ±1°C/°F (temperature) |
| Resolution | 0.01% (≤9.99%), 0.1% (≥10.0%) |
| Temperature Compensation Range | 5–100°C |
| Output | DC 4–20 mA, RS-232C |
| Light Source | LED (approx. 589 nm, D-line equivalent) |
| Prism Material | Synthetic Sapphire |
| Body Material | SUS316L Stainless Steel |
| IP Rating | IP67 |
| Dimensions | 160 × 167 × 110 mm |
| Weight | 2.4 kg |
| Power Supply | DC 24 V (AC 100 V optional with AD-32 adapter) |
| Measurement Interval | ~1 s (configurable to 5 presets) |
| Environmental Operating Temp. | 5–40°C |
Overview
The ATAGO CM-800α-SW In-Line Salinometer is a high-precision, process-integrated optical sensor engineered for continuous, real-time monitoring of sodium chloride (NaCl) concentration in aqueous salt solutions. Based on the principle of critical-angle refractometry—measuring the refractive index (nD) at the interface between the sample and a synthetic sapphire prism—the instrument delivers stable, temperature-compensated salinity readings across dynamic industrial environments. Unlike offline titration or conductivity-based methods, this device eliminates sampling delays, operator dependency, and calibration drift by performing non-invasive, in-situ measurement directly within pressurized or gravity-fed pipelines. Its design conforms to fundamental metrological requirements for process analytical technology (PAT), supporting consistent quality assurance in food processing, pharmaceutical buffer preparation, seawater desalination pre-treatment, electroplating bath control, and marine aquaculture systems.
Key Features
- Optical refractometric measurement with LED light source centered near the sodium D-line (589 nm), ensuring high spectral stability and long-term repeatability.
- Automatic Temperature Compensation (ATC) over 5–100°C range, using an integrated Pt100-grade temperature sensor embedded adjacent to the prism interface.
- Robust wetted materials: sapphire prism (Mohs hardness 9) and SUS316L stainless steel body, rated IP67 for dust-tight and temporary immersion resistance.
- Dual-output capability: isolated 4–20 mA analog signal (HART-compatible wiring) for PLC/DCS integration, plus RS-232C serial interface for configuration, diagnostics, and raw refractive index data export.
- Configurable measurement interval (default 1 second; five preset options available) to match process dynamics without compromising data fidelity.
- Modular mechanical design compatible with L-type and straight-pipe mounting configurations, enabling retrofit installation without process shutdown.
Sample Compatibility & Compliance
The CM-800α-SW is validated for use with homogeneous, non-particulate, low-viscosity aqueous NaCl solutions—including brine, pickling solutions, cooling tower makeup water, and saline cleaning agents. It is not intended for slurries, emulsions, or highly turbid media that may scatter incident light or foul the prism surface. The instrument complies with IEC 61000-6-2 (electromagnetic immunity) and IEC 61000-6-4 (emission) standards. Its analog output meets NAMUR NE43 signaling conventions. While not certified for SIL-rated safety functions, its architecture supports GLP/GMP-aligned operational qualification (OQ) protocols when deployed with documented calibration traceability to NIST-traceable refractometric standards.
Software & Data Management
Configuration and firmware updates are performed via ATAGO’s proprietary PC-based utility (CM-ConfigTool), which runs on Windows OS and supports secure parameter locking, alarm threshold definition (HI/LO), and data logging export in CSV format. RS-232C communication allows direct integration with SCADA systems using Modbus RTU (via optional protocol converter) or custom ASCII command sets. Audit trails—including calibration events, parameter changes, and output deviations—are retained in non-volatile memory and can be retrieved for FDA 21 CFR Part 11 compliance when paired with validated electronic record systems. No cloud connectivity or remote access functionality is embedded; all data handling remains on-premise per industrial cybersecurity best practices.
Applications
- Real-time control of brine concentration in meat curing, fish salting, and vegetable fermentation lines.
- Monitoring NaCl levels in pharmaceutical isotonic saline production (USP <788> particulate limits apply separately).
- Process optimization in chlor-alkali electrolysis feedstock preparation.
- Quality verification of de-icing solutions prior to distribution.
- Automated feedback control of seawater dilution ratios in recirculating aquaculture systems (RAS).
- Validation of cleaning-in-place (CIP) rinse endpoint detection in dairy and beverage facilities.
FAQ
What measurement principle does the CM-800α-SW employ?
It uses critical-angle refractometry, correlating the refractive index of the sample to NaCl mass concentration using a pre-characterized polynomial calibration curve traceable to reference standards.
Can the device measure other dissolved solids besides NaCl?
No—it is factory-calibrated exclusively for aqueous sodium chloride solutions. Cross-sensitivity to sugars, alcohols, or acids will produce inaccurate readings; alternative CM-800α variants exist for those analytes.
Is routine prism cleaning required?
Yes—while sapphire resists scratching, organic fouling or mineral scaling must be removed periodically using deionized water and lint-free wipes; ATAGO recommends inspection intervals aligned with process fouling propensity.
Does the unit support hazardous area certification?
Not natively—the standard model lacks ATEX or IECEx certification; explosion-proof enclosures or remote sensor configurations require third-party engineering review.
How is calibration verified in situ?
Users perform two-point verification using certified NaCl standard solutions (e.g., 5.00% and 20.00% w/w); deviation beyond ±0.15% triggers full recalibration using ATAGO’s service procedure and master reference cell.
