OUSAF46

Summary

Product identification

Product Name: OUSAF46 Description: Optical sensor with the OUA260 flow assembly for the measurement of UV absorption. Manufacturer: Endress+Hauser

Application

The OUSAF46 sensor measures spectral absorption in the ultraviolet region of the electromagnetic spectrum for process liquids.

• Measurement of protein concentrations
• Chromatography monitoring
• Filtration monitoring
• Concentration measurement of organic compounds
• Detection of aromates

Benefits

• Improved process control and quality control via quick and reliable monitoring of product concentration.
• Measuring range up to 2.5 AU or 50 OD (depending on optical path length).
• Measurement of UV absorption at discrete wavelengths between 254 nm and 313 nm.
• Outstanding filter properties for highest linearity.
• Direct concurrence with laboratory values.
• Integrated reference detector for lamp compensation.
• Gas discharge lamp for long service life and stable measured values.
• FM- and ATEX-approved lamps available for hazardous areas.
• Hygienic design and FDA- and USP-compliant sealing materials for life sciences sector.
• SIP/CIP-resistant for high product safety.
• Low volume requirements for high product yield.
• Wide range of materials and process connections for maximum durability.
• Optional air purge ports to prevent condensate formation on optical windows.

Function and system design

Measuring principle

The sensor operates based on the Lambert-Beer law, which describes the linear dependency between light absorption and the concentration of the absorbing substance. The formula is:

A = -log(T) = ε . c . OPL

Where:

• A = Absorption
• T = Transmission (I/I₀)
• I = Intensity of received light at detector
• I₀ = Intensity of transmitted light of light source
• 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 conversion to absorbance units (AU, OD) is performed by an associated transmitter. The OUSAF46 has two pairs of reference and measuring detectors.

A typical measuring system comprises:

• Sensor (photometer) OUSAF46
• Transmitter (e.g., Liquiline CM44P)
• Cable set (e.g., CUK80)
• Assembly (e.g., OUA260)

Input

• Measured variable: UV-absorption
• Measuring range:
  • 0 to 2.5 AU
  • Max. 50 OD (depending on the optical path length)
• Wavelength: Discrete wavelength combination at 254/280, 280/295, 280/302 or 280/313 nm.

Electrical connection

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

Lamp voltage

• Lamp type: Low-pressure mercury lamp
• Lamp voltage: 10.0 ± 0.1 V

Cable length

• Maximum 100 m (330 ft)

Versions for use in hazardous areas

This section applies only to measuring points consisting of the OUSAF46 photometer, CUK80 cable set, and a Liquiline CM44P transmitter.

• Detector: Intrinsically safe silicon photovoltaic cells, deployable in Zone 1 and Class I, Division 1 environments. A safety barrier (e.g., MTL7760AC) separates the safe and hazardous areas. The sensor cable shield is connected to the ground terminal of the barrier.
• Lamp: Hazardous area lamps require connection via a certified junction box.
  • For FM approval, the junction box is included and pre-terminated on the lamp side.
  • For ATEX approval, the junction box and cable glands must be provided by the customer.

Mounting

Installation instructions

The sensor should be mounted at an appropriate angle within the pipe to ensure optimal performance. Various mounting angles are presented, with "B" being the optimum and "E" being forbidden.

Environment

• Ambient 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, depending on materials, pipe size, and process connection of the flow assembly.

Mechanical construction

Design, dimensions

• Sensor module: Composed of lamp, detector, and assembly.
  • Standard lamp dimension (A): 146.1 mm (5.75 inches)
  • Standard detector dimension (B): 80 mm (3.15 inches)
  • Easycal detector dimension (B): 94 mm (3.70 inches)
• Allow an additional gap of 5 cm (2 inches) on both the lamp and detector sides for cable connection.
• Dimensions for the OUA260 assembly are detailed in Technical Information TI00418C.

Weight

• Sensor (UV lamp): 0.58 kg (1.28 lbs)
• Sensor (UV lamp with wire-braided cable and junction box for hazardous area): 3.2 kg (6.66 lbs)
• Easycal detector: 0.53 kg (1.17 lbs)
• Standard detector: 0.78 kg (1.71 lbs)

Materials

• Sensor housing: Stainless steel 316
• Cable connector ends: Nickel-plated brass
• Light source: Low-pressure mercury lamp (typical operating life: 3000 h; requires 30 minutes warm-up)
• Detector: UV silicon detector, hermetically sealed
• Filter: Multilayer interference filter

Certificates and approvals

Current certificates and approvals can be selected via the Product Configurator at www.endress.com.

Ordering information

The Product Configurator at www.endress.com/ousaf46 can be used to configure and order the device.

Scope of delivery

The scope of delivery includes the detector and lamp module, either separate or mounted on a flow assembly, and operating instructions. If a calibration option is selected for the transmitter, the complete measuring system is factory-calibrated and shipped as one package.

Accessories

Flow assembly

• OUA260: For sensor installation in pipes, available with various materials, process connections, and path lengths.
• CUA261: VARIVENT adapter for installation in VARINLINE housing, suitable for CIP/SIP.

Cable

• CUK80 cable set: Pre-terminated and labeled cables for connecting analog photometer sensors.

Calibration

• Kit OUSAF46 EasyCal retrofit kit: Patented system traceable to NIST for UV absorption sensor calibration. Available for different wavelength pairs:
  • 254/280 nm: 71382018
  • 280/295 nm: 71382019
  • 280/313 nm: 71382020
• Reference rod: Order number 71108543

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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