Turbimax CUS51D

Summary

Product identification

• Product Name: Turbimax CUS51D
• Type: Sensor for turbidity and solids content
• Document ID: TI00461C/07/EN/19.23-00
• Date: 2023-11-15

Application

The Turbimax CUS51D is a sensor designed for various wastewater treatment applications, including:

• Turbidity measurement in outlets
• Solids content in sludge activation and recirculation
• Solids content in sludge treatment
• Filterable matter in WWTP outlets

Benefits

• Versatile Measurement Principles: Incorporates 90°, 135°, and 4-beam pulsed light methods for optimal adaptation to specific measurement tasks.
• Easy Commissioning: Factory calibrated (based on formazine) with pre-calibrated application settings.
• Plug and Play: Standardized Memosens technology enables simple connection and data transfer.
• Intelligent Sensor: Stores all characteristic and calibration data internally.
• Flexible Calibration: Supports customer calibrations with 1 to 5 points, performable in the lab or on-site.

Measuring Principle

The sensor operates by directing a light beam through the medium. Particles in the medium scatter this light. The amount and angle of scattered light are used to determine turbidity and solids content.

• 90° Scattered Light: Primarily used for turbidity measurement in drinking water.
• 135° Scattered Light (Backscattered): Extends the dynamic range for high particle densities and is used for measuring high turbidity values.
• 4-Beam Pulsed Light Method: Utilizes two light sources and four receivers to minimize interference from fouling, extraneous light, and LED aging.

Measuring System

A complete measuring system includes the Turbimax CUS51D sensor, a Liquiline CM44x multi-channel transmitter, and an assembly such as the Flexdip CYA112 with CYH112 holder or a retractable assembly like Cleanfit CUA451.

Input

• Measured Variables: Turbidity, Solids content, Temperature

• Measuring Range:

  • CUS51D-**C1:
    • Turbidity (Formazine): 0.000 to 4000 FNU (display range up to 9999 FNU)
    • Solids content (Kaolin): 0 to 5 g/l
    • Temperature: –20 to 80 °C (–4 to 176 °F)
  • CUS51D-**D1:
    • Turbidity (Formazine): 0.000 to 4000 FNU (display range up to 9999 FNU)
    • Solids content: 0 to 300 g/l (0 to 2.5 lb/gal) or 0 to 30 % (depending on application)
    • Temperature: –20 to 80 °C (–4 to 176 °F)

• Note: Achievable ranges for solids content depend heavily on the specific media.

Performance Characteristics

• Reference Operating Conditions: 20 °C (68 °F), 1013 hPa (15 psi)
• Maximum Measured Error:
  • Turbidity: < 2% of measured value or 0.1 FNU (whichever is greater)
  • Solids: < 5% of measured value or 1% of upper range value (whichever is greater), for sensors calibrated to the observed range.
• Repeatability: < 0.2% of reading
• Factory Calibration: Standard 3-point calibration for FNU and NTU.
• Drift: Largely drift-free due to electronic controls.
• Detection Limits:
  • Formazine: 0.006 FNU (0-50 FNU range), 0.4 FNU (0-4000 FNU range)
  • Kaolin: 0.85 mg/l (0-5000 mg/l range)

Applications and Recommended Operating Ranges

The sensor is factory calibrated for Formazine. Other applications are pre-calibrated and may require up to 5-point calibration.

• Clear Water Applications:

  • Formazine: 0 to 4000 FNU
  • Kaolin: 0 to 5 g/l
  • SiO₂: 5 to 100 g/l
  • TiO₂: 0.2 to 150 g/l

• Solids Applications:

  • Thin sludge: 0 to 5 g/l
  • Activated sludge: 2 to 15 g/l
  • Excess sludge: 3 to 50 g/l
  • Sludge, general: 0 to 50 g/l
  • Digested sludge: 5 to 100 g/l / 300 g/l

• Note: For solids, actual achievable error margins depend on the media composition. Highly inhomogeneous media can lead to fluctuations and increased error. Multiple scattering can occur in formazine, kaolin, and thin sludge applications.

Mounting and Installation

• Installation Options: Retractable assembly (Cleanfit CUA451), Wastewater assembly (Flexdip CYA112), Flow assembly (Flowfit CYA251).
• Installation Angle: Maximum 90° (recommended 75° for retractable assembly), 45° or 90° for wastewater assembly. Optical windows should align with flow direction.
• Pipe Installation: Recommended in ascending pipes; possible in horizontal pipes. Avoid areas with air bubbles or sedimentation. For turbidity < 200 FNU, backscattering from pipe walls may distort measurements, requiring adjustment.
• Process Pressure: Maximum 2 bar (29 psi) for manual retraction.

Environment

• Ambient Temperature Range: –20 to 60 °C (–4 to 140 °F)
• Storage Temperature: –20 to 70 °C (–4 to 158 °F)
• Degree of Protection: IP 68, IP 66, Type 6P

Process

• Process Temperature Range: –5 to 50 °C (23 to 122 °F); up to 80 °C (176 °F) for short periods (1 h).
• Process Pressure Range: 0.5 to 10 bar (7.3 to 145 psi) absolute.
• Compressed Air Cleaning Pressure: 1.5 to 2 bar (21.8 to 29 psi) absolute.
• Minimum Flow: No minimum flow required, but sufficient mixing is recommended for media prone to deposits.

Mechanical Construction

• Dimensions: See diagrams (engineering units: mm (in)).
• Weight: Approx. 0.7 kg (1.5 lb) without cable.
• Materials:
  • Sensor Body: Stainless steel 1.4404 (AISI 316 L) or 1.4571 (AISI 316 Ti)
  • Optical Windows: Sapphire
  • O-rings: EPDM
• Process Connections: G1 and NPT ¾"
• Compressed Air Cleaning Connections: 6 mm (0.24 in), 8 mm (0.31 in), or 6.35 mm (0.25 in)

Certificates and Approvals

• CE mark
• NAMUR NE 21
• IEC 61010-1
• cCSAus General Purpose

Ordering Information

• Scope of Delivery: 1 sensor (version as ordered), 1 x Operating Instructions.
• Accessories: Include assemblies (FlowFit CUA120, Flexdip CYA112, Cleanfit CUA451, Flowfit CYA251), holders (Flexdip CYH112), compressed air cleaning units, compressors, and Memosens data cables (CYK11).

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Disclaimer: This extraction may miss figures, footnotes, or revisions. Contractual data must match the OEM PDF revision used on the project.

Official datasheet (PDF)

Lenntech datasheet mirror