What is UV Transmittance (UVT)?

UV Transmittance refers to the percentage of light at the wavelength of 254 nm that passes through a sample of water. UVT relates to the organics, colloidal solids, and suspended particles that absorb and scatter this wavelength of UV light. The amount of UV light absorbed by the sample is known as UV Absorbance (expressed as A254). Absorbance and transmittance are related by a logarithmic function A = log10 (1/T).

How is UVT Measured?

Ultraviolet (UV) light, at the wavelength of 254 nm, is passed through a path of a 1 cm water sample. Compared to a light intensity being measured in pure water and displaying a percentage, the intensity of light is measured beside a photodiode.

Why is UVT Measurement Necessary?

UV Transmittance measurements provide valuable information related to the amount of natural organic matter (NOM) in the water sample. Data characterizing the organics content of the sample water can be used to control and optimize water and wastewater treatment processes. Generally, UVT measurements are used to optimize energy efficiency and to ensure adequate dosing by the UV disinfection system. UV dose is dependent on the UV light intensity, contact time (controlled by flow rate), and UVT. Most UV disinfection systems are programmed for a 4-20 mA input of UVT to balance lamp intensity for the system meets dosing requirements.

Common Applications:

  • UV disinfection performance optimization in wastewater
  • Dose control in drinking/process water
  • Sizing and design of UV disinfection systems
  • Selection of the optimal disinfection treatment process
  • Disinfection by-product (DBP) formation potential upstream to chlorination
  • Micropollutant removal efficiency of wastewater treated with ozone
  • Optimize chemical dosing for turbidity and organics removal
  • Source water quality monitoring at influent to drinking water treatment plant
  • Filtration membrane protection from biofouling

HIGH PERFORMANCE UV-C LED TECHNOLOGY

Instant LED illumination offers many advantages over traditional mercury lamps:

  • Up to 5x longer lifetime
  • Never hassle with lamp changes or field-serviceable parts
  • Environmentally-friendly & manufactured with no mercury
Reliable UVT Sensor

UVT-LED-PW

Inline Process UV Transmittance Monitor

uv transmittance monitor
  • Optimize Dosing Efficiency of UV Disinfection
  • Automatic Cleaning & Calibration
  • Simple Connectivity with Direct 4-20mA Output
  • Convenient Small Footprint Design

UVT-LED-SW

Submersible UV Transmittance Monitor

wastewater UV transmittance meter
  • Designed for Wastewater UV Disinfection Optimization
  • Automatic Cleaning & Calibration
  • No Expensive Annual Maintenance Contracts
  • Effortless Installation or Retrofitting

UVT-LED-H

Handheld/Portable UV Transmittance Monitor

portable uv transmittance
  • Obtain UV Transmittance Measurements Anywhere
  • Verify Online UVT Sensor Performance
  • Zero Warm-up Time
  • Simple Push Button Operation

TECH SPECS

POWER: 24 VDC, Output: 4-20mA

SIZE & WEIGHT: 7.55″H x 2.56″ Dia, 1.6 lbs (0.73 kg)

MEASUREMENTS: Range: 10% – 100% T, Interval: 60 seconds

MAINTENANCE: Inspection Interval: 6 months, 1 hour/month, typical

WARRANTY: 2 Year Limited Warranty

Measurement Path Length: 1cm

Accuracy: 1.0% T

Resolution: 0.1% T

Display: LCD with LED Backlight

IP Ingress Rating: IP66

POWER: 24 VDC, Output: 4-20mA

SIZE & WEIGHT: 9.40″H x 3.00″ Dia, 1.78 lbs (0.81 kg)

MEASUREMENTS: Range: 10% – 100% T, Interval: 60 seconds

MAINTENANCE: Inspection Interval: 3 months, 1 hour/month, typical

WARRANTY: 2 Year Limited Warranty

Measurement Path Length: 1cm

Accuracy: 1.0% T

Resolution: 0.1% T

Display: Optional 4-20mA Display (Sold Separately)

IP Ingress Rating: IP68

Battery Life: Up to 350 readings on a single charge

SIZE & WEIGHT: 7.55″H x 2.56″ Dia, 0.9 lbs (0.41 kg)

MEASUREMENTS: Range: 10% – 100% T, Interval: 30 seconds

MAINTENANCE: Inspection Interval: 1 hour/month, typical

WARRANTY: 2 Year Limited Warranty

Measurement Path Length: 1cm

Accuracy: 1.0% T

Resolution: 0.1% T

Display: LCD with LED Backlight

IP Ingress Rating: IP66