Liquiline System CA80COD

Summary

Product identification

The Liquiline System CA80COD is a wet-chemical analyzer designed for the determination of chemical oxygen demand (COD) in liquid media.

Application

This analyzer is suitable for:

• Monitoring of wastewater treatment plant inlets
• Control of municipal wastewater treatment
• Monitoring of industrial wastewater
• Control of industrial wastewater treatment

The "Cabinet, outdoor version" is designed for outdoor installation.

Features and Benefits

• Integrated controller with digital Memosens technology
• Upgradeable to a measuring station by connecting up to 4 Memosens sensors
• High-precision dosing unit
• Automatic measuring range switching: 10 to 5000 mg/l O₂
• Supports digital fieldbuses including PROFINET, PROFIBUS DP, Modbus TCP, Modbus RS485, and EtherNet/IP, along with a web server.

Measuring Principle

The COD is determined by digesting the sample at 175 °C using sulfuric acid, silver sulfate (as a catalyst), and potassium dichromate (a strong oxidizing agent). Mercuric sulfate is added to remove interfering chloride ions. The reduction of Cr⁶⁺ to Cr³⁺ during this process causes a color change from orange to green, which is measured optically. The pressure reactor of the CA80COD can shorten the digestion time.

Cross-sensitivity: No cross-sensitivities were observed up to the following concentrations:

• (NH₄)₂SO₄: 20,000 mg/l (ppm)
• NaCl: 5,000 mg/l (ppm)

Measuring System Components

A complete measuring system includes:

• Analyzer Liquiline System CA80COD
• Reagents and standard solutions (ordered separately)
• Suction strainer or optional Y strainer with process connection

Electrical Specifications

Input

• Measured Variables: CSBcr O₂ [mg/l, ppm]
• Measuring Range:
  • CA80COD-**C4: 0 to 500 mg/l O₂, automatic measuring range switching
  • CA80COD-**C5: 0 to 5000 mg/l O₂, automatic measuring range switching
  • CA80COD-**C6: 0 to 5000 mg/l O₂ + dilution module (1:4)
• Types of Input:
  • 1 measuring channel (analyzer main parameter)
  • 1 to 4 digital sensor inputs for sensors with Memosens protocol (optional)
  • Analog current inputs (optional)
  • Binary inputs (optional)
• Analog Current Input:
  • 2 x 0/4 to 20 mA, passive, potentially isolated
  • Span: > 0 to 20 mA
  • Signal characteristic: Linear
• Memosens Sensor Cable:
  • Type: Memosens data cable CYK10 or sensor fixed cable
  • Max. cable length: 100 m (330 ft)

Output

• Analog Current Output:
  • Standard: 2 x 0/4 to 20 mA, active, potentially isolated
  • Optional: 4 x 0/4 to 20 mA, active, potentially isolated
  • Optional: 6 x 0/4 to 20 mA, active, potentially isolated
  • Load: Max. 500 Ω
• Relay Outputs:
  • 1 single-pin changeover contact (alarm relay) standard
  • 2 or 4 single-pin changeover contacts (optional with extension modules)
  • Maximum load: 0.5 A (alarm relay), 2.0 A (other relays)
  • Switching capacity varies by voltage and load – see documentation for specifics.

Power Supply

• Supply Voltage: 100 to 120 V AC / 200 to 240 V AC, 50 or 60 Hz
• Power Consumption:
  • All versions except "Outdoor": 250 VA
  • "Outdoor" version: 250 VA + 650 VA per hose heater (max. 900 VA with cooling)

Communication

• Fieldbus Systems: PROFIBUS DP (Profile 3.02), Modbus TCP, Modbus RS485, PROFINET, EtherNet/IP
• Configuration: Via Ethernet, HART, PROFIBUS DP, Modbus RS485, or Web Server.
• Web Server: TCP port 80, accessible via WiFi/WLAN/LAN/GSM/3G routers. Allows remote configuration, logbook export, etc.

Mechanical / Hydraulic Specifications

Dimensions

See official PDF for detailed dimensions drawings.

Weight

Approx. 40 kg (88 lbs)

Materials

• Parts not in contact with medium: ASA + PC, PP, Safety glass (coated), EPP, Powder-coated sheet steel.
• Parts in contact with medium: PP, TPE, ETFE, FKM, Borosilicate glass, PTFE, PVDF, FFKM, PE, PVC-U.

Process Connections

• Sample Inlet: Hose gland for rigid hoses with OD 3.2 mm
• Dilution Water: Hose gland for rigid hoses with OD 3.2 mm
• Outlet: Hose gland for rigid hoses with OD 6 mm

Hose Entries

• 4 x bores for M32 for sample inflow and outflow

Environmental Conditions

• Ambient Temperature:
  • Standard housings: +5 to +40 °C (41 to 104 °F)
  • Outdoor version: -20 to +40 °C (-4 to 104 °F)
• Storage Temperature: –20 to 60 °C (–4 to 140 °F)
• Relative Humidity: 10 to 95 %, non-condensing
• Degree of Protection: IP55 (cabinet, analyzer stand), TYPE 3R (cabinet, analyzer stand)

Data Logging

• Integrated Ring/Stack Memories: For analog values, events, analyzer data logbook.
  • Max. 2 data logbooks, 20,000 entries per logbook.
• Digital Sensors Data Logbooks: Max. 8 data logbooks, 150,000 entries per logbook.
• Other Logbooks: Calibration (max. 75 entries), Hardware (max. 125 entries), Version (max. 50 entries), Event (max. 19,500 entries), Operations (max. 250 entries), Diagnostic (max. 250 entries).
• SD Card: For software updates, data storage, and configuration transfer.

Self-Monitoring Functions

• Electronics monitoring (current inputs, board voltages, board temperature)
• Counters for consumables
• Photometer temperature and communication monitoring
• Leak sensor in housing

Performance Characteristics

• Maximum Measured Error (COD):
  • 0 to 30 mg/l (ppm): 1.5 mg/l (ppm)

  • 30 to 50 mg/l (ppm): 3 mg/l (ppm)

  • 50 to 100 mg/l (ppm): 6 mg/l (ppm)

  • 100 to 200 mg/l (ppm): 8 mg/l (ppm)

  • 200 to 400 mg/l (ppm): 4% of reading

  • 400 to 5000 mg/l (ppm): 3% of reading

• Limit of Quantification (LOQ): 15 mg/l (ppm) O₂
• Repeatability: ± 5 % of measured value
• Measuring Interval: Continuous (approx. 55 min), adjustable from 30 min to 24 h.
• Digestion Time: 3 to 120 min
• Sample Requirement: 8 ml/measurement
• Reagent Consumption: One set of reagents lasts approx. 50 days at a 1-hour measuring interval.
• Calibration Interval: 1 h to 90 days.
• Maintenance Interval: Weekly visual inspection, monthly 1 hour effort.

Disclaimer

This summary is extracted from a datasheet and may not include all figures, footnotes, or revisions. Contractual data must be confirmed against the specific OEM PDF revision used for the project.

Official datasheet (PDF)

Lenntech datasheet mirror