OUSAF12

Summary

Product identification

• Product Name: OUSAF12
• Product Type: Optical sensor combined with the OUA260 flow assembly for absorbance measurement.
• Document ID: OUSAF12 / TI00497C/07/EN/03.21

Application

The OUSAF12 sensor is designed for determining the VIS/NIR absorption of liquid media. It is applicable in:

• Suspended solids measurement
• Pharmaceuticals and biotechnology
• Chemical industry
• Paper and pulp industry
• Interphase detection
• Food and beverage industry
• Oil and gas industry
• Centrifuge and separator control

Your benefits

• Reliable absorption measurement for quality control and enhanced production efficiency.
• Measuring range up to 2.5 AU or 50 OD (depending on optical path length).
• Configurable for discrete wavelength measurements in the visible and NIR regions.
• Color-independent measurement capability with an optional broadband filter.
• Long service life and stable measurements due to an incandescent lamp.
• Cost-effective, time-efficient, liquid-free verification.
• FM- and ATEX-approved lamps for hazardous area applications.
• Durable and deployable in various applications with a variety of materials and process connections.
• Hygienic design with certified materials and CIP/SIP resistance for high product safety.
• Optional air purge ports to prevent condensate formation on optical windows.

Function and system design

Measuring principle

The sensor operates on the principle of light absorption, based on the Lambert-Beer law. This law establishes a linear relationship between light absorption and the concentration of the absorbing substance:

A = -log(T) = ε . c . OPL

Where:

• T = Transmission (I/I₀)
• I = Intensity of received light at the detector
• I₀ = Intensity of transmitted light from the light source
• A = Absorption
• ε = Extinction coefficient
• c = Concentration
• OPL = Optical path length

A light source emits radiation through the medium, and the incident radiation is measured by a detector. The light intensity is converted to a photocurrent by a photodiode, and subsequent conversion to absorbance units (AU, OD) is performed by an associated transmitter.

Measuring system

A complete measuring system comprises:

• Sensor (photometer): OUSAF12
• Transmitter (e.g., Liquiline CM44P)
• Cable set (e.g., CUK80)
• Assembly (e.g., OUA260)

Input

• Measured variable: Process-absorption
• Measuring range:
  • 0 to 2.5 AU
  • Max. 50 OD (depending on the optical path length)
• Wavelength: Broadband, NIR (780 nm+), 400 nm, 420 nm, 430 nm, 540 nm, 950 nm, and 1134 nm

Power supply

The sensor connects to the transmitter via a pre-terminated or labeled cable set CUK80 (for CM44P) or OUK10 (for CVM40). Cable set must be ordered separately. Do not shorten or modify the CUK80 cable.

Electrical connection

• Cable length: Maximum 100 m (330 ft)
• Lamp voltage: Varies by sensor version (e.g., 3.4 ± 0.1 V or 4.9 ± 0.1 V). See table in the original document for specific lamp types and voltages.

Versions for use in hazardous areas

• Applicable for measuring points with a photometer, CUK80 cable set, and Liquiline CM44P transmitter.
• Detectors (silicon photovoltaic cells) are intrinsically safe for Zone 1 and Class I, Division 1 environments.
• Requires a safety barrier (e.g., MTL7760AC) to separate hazardous and safe areas.
• Hazardous area lamps connect via a certified junction box.

Installation

Mounting angles

The orientation of the sensor relative to the pipe flow is critical for optimal performance. An optimum mounting angle (B) is recommended, with suitable (A) and acceptable (C) angles also noted. Angles to be avoided (D) and forbidden angles (E) are shown.

Environment

• Atmospheric temperature: 0 to 55 °C (32 to 131 °F)
• Storage temperature: -10 to +70 °C (+10 to +160 °F)
• Humidity: 5 to 95 %
• Degree of protection: IP 65 (NEMA 4) for all optical parts

Process

• Process temperature: 0 to 90 °C (32 to 194 °F) continuous; Max. 130 °C (266 °F) for 2 hours.
• Process pressure: Max. 100 bar (1450 psi) absolute, dependent on material, pipe size, and process connection of the flow assembly.

Mechanical construction

Design, dimensions

Dimensions of the sensor module depend on the lamp and detector types.

• Lamp dimension (A):
  • High-luminescence lamp or standard incandescent lamp: 33.78 mm (1.33")
  • Gas-filled lamp: 33.78 mm (1.33")
  • Collimated incandescent lamp: 151.3 mm (5.96")
• Detector dimension (B):
  • Standard version with test filter: 101.6 mm (4.0")
  • Easycal: 101.6 mm (4.0")

An additional gap of 5 cm (2") on both lamp and detector sides is required for sensor cable connection.

• Weight: 1.225 kg (2.7 lbs.), without flow assembly.

Materials

• Sensor housing: Stainless steel 316L
• Cable connector ends: Nickel-plated brass

Light source

• Various lamp types available (High-luminescence, Gas-filled high-performance, Collimated incandescent, Standard incandescent).
• Lamp operating life: Typically 10,000 hours.
• Warm-up period of 30 minutes required for full lamp capacity.

Detector

• Silicon detector, hermetically sealed.

Filter

• Multilayer narrow-band interference filter.

Certificates and approvals

Current certificates and approvals can be found via the Endress+Hauser Product Configurator on www.endress.com.

Ordering information

Product information and configuration tools are available at www.endress.com/ousaf12.

Scope of delivery

The scope of delivery varies based on the ordered version and may include the detector and lamp module with or without the OUA260 flow assembly, and Operating Instructions. Factory calibration of the complete measuring system is available if selected during configuration.

Accessories

• Flow assembly: OUA260, CUA261
• Cables: CUK80 cable set, OUK10 cable set

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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