Search This Site

(Search by Product Type i.e. Level or Brand Name i.e. Walchem)

Hallett 4-20mA Wastewater System

UV Pure’s Hallett® 4-20mA Wastewater System, was developed for residential and light commercial wastewater treatment applications, outperforms all conventional UV systems with the ability to treat very low quality wastewaters (low UV transmittance) trouble free.
Standard equipment with this is model is the 4-20mA Unit that allows for remote monitoring of your Hallett system. It provides an analog output of UV Intensity and Net UV Transmittance (UVT) from a Hallett system. The loop-powered transmitter can be used with any device that requires a 4-20mA signal for logging purposes or for process control.


Hallett UV wastewater purification systems, with patented Crossfire Technology, are engineered for simple, efficient multiplex configuration, and treat flows up to 1 MGD (3785 m³/day) for wastewater and reuse applications. Hallett LPHO (low pressure high output) wastewater systems outperform all conventional LPHO wastewater systems and most medium pressure systems with the ability to treat very low quality (low UV transmittance) wastewaters trouble free. Traditionally, low-quality wastewater effluents have required medium pressure systems to reach the required dose. The Hallett wastewater system is the first of its kind and the only LPHO technology that matches and/or beats the performance of conventional medium pressure systems which are significantly more expensive from a capital and operating cost perspective. Each Hallett system for wastewater is factory sized and programmed to achieve target treatment requirements. Hallett systems are effective in a broad range of pre-treatment wastewater quality. They are also engineered to prevent operator exposure to potentially hazardous wastewater since no manual quartz cleaning is required. The Hallett 4-20mA offers these unique product features:

  • LCD Display - an LCD display is a standard feature indicating both UV Sensors’ input values and transmitted values.

  • UV Intensity Output – a normalized signal (0-100%) proportional to the UV intensity of the UV lamp is transmitted.

  • Net UV Transmittance (UVT) Output – a normalized signal (0-100%) proportional to the Net UV Transmittance of the water is transmitted.

  • Factory Calibrated – both span and offsets are preset for immediate field use.

  • Mounted On Board – the 4-20mA unit is installed within the Hallett 30 unit with the display located on the front panel.

Broadest Range of Pre-treatment Conditions
Parameter Pre-Treat Conditions
TSS < 20 mg/L
BOD < 20 mg/L
Turbidity < 4 NTU
UVT As low as 45%



  • 4-20mA Unit

  • Flexible stainless steel hook-up hoses

  • Power Conditioner


  • Wireless Remote Monitor

  • Automatic Shut-off Solenoid Value

  • Hallett Diagnostic Tool

  • Purge Valve


Model Hallett 30-1.5" (WW) w/ 4-20 mA
PART NUMBER (115 Volt) C000019
PART NUMBER (240 Volt) C000024
Validation / Certification Engineered to meet dosing and disinfection requirements of wastewater effluent. Typically a minimum dose of 30 mJ/cm2 to reduce coliform to < 200 counts / 100ml. Higher doses available for re-use and non-detect applications ( < 2 counts / 100 ml). In use on Title 22 applications. Approved by the MENV for use in Quebec.. Certified to AB 1953.
UV Dose Minimum dose of 30 mJ/cm2 at end of lamp life
Minimum UV Transmittance 45%
Max Flow Rate 25 US gpm (95 L/min) (5.68 m3/hr) @ 65% UVT, 30 mJ/cm2 dose (flow rates depend on required dose and source water UVT)
Water Pressure 0 psi (69 kPa) to 100 psi (690 kPa); units are tested to 240 psi (1.6 MPa)
Dynamic Flow Restrictor No internal restrictor installed
Pressure Drop at 75% of nominal flow capacity 1 psi (7 kPa)
Multiplexed Flow Capacity Engineered for multiple systems in parallel, for flow rates up to 1 MGD (696 US gpm) (2629 L/min) (158 m3/hr)
Redundancy Additional backup systems can be added cost effectively
Solenoid Shut-Off Valve Automatic shut-off valve available as option
Inlet and Outlet Connections 1.5" flexible FIP connection for easy installation
Voltage Models available in either 115V or 240V configurations (please see different part numbers above)
Protection from Power Fluctuations 115V Models include power conditioner that meets UL 1449. External power conditioner recommended on 240V models
Maximum Power Consumption 175W
Electrical Certification Intertek ETL (UL, ULC and CE equivalent)
Lamps Low pressure, high output proprietary lamps contain up to 30 mg of mercury (Hg); rated for 9000 hours (1 year) of continuous use
Maintenance Onboard 9000 hour lamp life with lamp hour countdown to end of life. Automatic self-cleaning device prevents quartz sleeve from fouling and requires no maintenance
Electronic Ballast Auto power-regulated smart ballast; protected from power fluctuations
Self-Cleaning Stainless Steel patented automatic wiper-blade system keeps quartz free from scaling or bio-film
On-Board Micro-Processor and Monitor Patented dual smart UV sensors continuously monitor UV dose, lamp intensity (UVI) and water transmittance (UVT); on-board LED's indicate system status: OK, warning or alarm conditions. Optional External digital monitor (HDT) displays above in millivolts.
4-20 mA Analog Output Installed as standard. Provides two analog signals (4-20 mA) for both UV Intensity (UVI) and water UV Transmittance (UVT) and allows for dose to be calculated in real time.
Dry Contacts Included as standard for remote alarms, auto-dialer integration, or similar.
Remote Alarm Included as standard on all models.
Dimensions (H, W, D) 32 x 8 x 10" (830 x 220 x 260 mm)
Weight - Dry 32 lbs (14.5 kg)
Weight - Wet 34.2 lbs (15.5 kg)
Warranty 1 year limited warranty on bulbs and sensor probes; 3 year limited warranty on electrical components and quartz sleeve; 5 year limited warranty for structural, hardware and mechanical components
EPA FIFRA Certified EPA Est. No. 075213-CAN-001
Patents Patented in US 6,707,048, Canada 2,463,503, Australia 2002333084, Mexico 248805, Patents pending in Europe, Eurasia, Japan, UK

Download Brochure


UV Pure's Crossfire Technology uses dual smart UV sensors that continuously monitor UV Dose, Lamp Intensity (UVI), and net UV Transmittance (UVT). That means a disinfection dose 2.4 times greater than conventional UV systems for the same energy input and cost.

UV Lamp removal is fast, safe and easy on all UV Pure systems like this Hallett 30 system for wastewater and potable water treatments. There is no extra, wasted space required for lamp removal. Hallett's are equipped with UV Pure's patented Crossfire Technology.

Flexible stainless steel hook-up hoses mean no hard piping and are standard on all UV Pure Hallett wastewater and potable water treatment systems.


Only UV Pure's patented Crossfire Technology provides automatic mechanical self-cleaning eliminating quartz fouling from minerals and bio-film. It also prevents operator exposure to potentially toxic wastewater. With Crossfire Technology there is no risk of false alarms due to fouling.


About Us

Metex Corporation Limited has been providing superior products and services to the process control, chemical treatment, waste water, industrial and manufacturing industries for over 25 years. It is our goal to continually provide our customers with the best possible equipment, technology, and service.


Our Products

Dataloggers, sensors, pumps, recorders, hand held instruments, flow instrumentation, level controls, valves, instrumentation, containers, tanks, transmitters, data loggers, digital indicators, mixers and agitators, pressure intrumentation, analyzers and controllers for a variety of industrial applications such as water quality, pH/ORP and more.

Website Content

Water Analyzers and Controllers, Wireless Products, Corrosion Monitoring Equipment, Cooling Tower and Boiler Controllers, a wide variety of Pumps, Valves, Dataloggers and Recorders, HVAC, Instrumentation, Skids and Systems, Containers and Tanks from world leading manufacturers are products you will find on this site.

Get in Touch