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Cerex UV Sentry

The Cerex UV SENTRY is an open-path gas analyzer that specializes in sensitive detection of key hazardous emissions such as Benzene and Chlorine over 1000+ meters of fence-line paths. It sets the industry standard for time-resolved, gap-less fugitive emissions and chemical emergency monitoring across fence lines, around process units, and around tank farms.

As the most cost-effective solution for part-per-trillion detection limits of Benzene-specific monitoring, the UV SENTRY is deployed world-wide by some of the world’s largest petrochemical companies, oil refineries, and government agencies.

Key Features

  • Benzene and other gases down to parts-per-trillion minimum detection limits (gas specific) within seconds – real-time data output
  • Low cost of ownership, no-maintenance design; only consumables are dust filters and UV lamp
  • Simple, inherent calibration verification using built-in flow cell
  • Raw data auto-archived in .csv format for instant analysis, compared to “black box” solutions
  • Remote control over network or internet – cellular-ready

Home » Multi-Gas Analyzers » UV Sentry Series

Cerex UV Sentry

0+m
of optical path length
0 gases
to monitor simultaneously
0 parts
that require regular maintenance

 

Standard

Weight 24.04kg (53lbs)
Enclosure type 4X – IP54, thermoelectrically cooled
Measurements

The UV Sentry is a parts per billion (ppb) to percent level chemical detection and quantification open-path UV-DOAS analyzer. It offers high-performing, time-resolved monitoring of a variety of regulated gases.

Operating Conditions

  • Temperature -40°F to 131°F (-40°C to 55°C)
  • Suitable for corrosive environment system deployment
  • Tripod mountable for semi-permanent installations
  • We recommend sheltering against wind and solar loading for permanent installations

Maintenance

  • Lamp replacement time is application specific (2000 hour guaranteed half-life)
  • Recommend monthly inspections of lamp, air filter and fans
  • Rinse air conditioner fins as needed
  • Fans are rated to 40,000 hours at 40°C
Coming soon – (PDF) Download Brochure


Harsh Climate


Based on years of the success with UV SENTRY, the Harsh Climate model was developed by Cerex’s engineers to meet the demand of open path analyzers that can output reliable data in the midst of extreme environmental conditions.

Utilizing the same proprietary technology, the Harsh Climate model features all the benefits of the UV Sentry (gas-specific parts per trillion detection limits, 1000+ meters of open path monitoring) inside a low-maintenance, reliable, and robust package.

General Specifications

  • Packaged in an type 4X – IP54, thermoelectrically cooled, enclosure (environmentally sealed)

Operating Conditions

  • Operating temperature range of -40°F to 131°F (-40°C to 55°C)
  • Suitable for corrosive environment system deployment
  • Tripod mountable for semi-permanent installations
  • We recommend sheltering against wind and solar loading for permanent installations

Maintenance

  • Lamp replacement time is application specific (2000 hour guaranteed half-life)
  • Recommend monthly inspections of lamp, air filter and fans
  • Rinse air conditioner fins as needed
  • Fans are rated to 40,000 hours at 40°C
(PDF) Download UV SENTRY Harsh Climate Brochure

Hazardous Location (HazLoc)


Weight
53lbs
Measurements
29 x 13.3 x 12.3 (in)
The HazLoc UV Sentry model is suited for explosive atmospheres, meeting the standards for North American C1 Div 2 A-D HAZLOC compliance.

HazLoc compliance is significantly important in environments where electrical equipment has the potential to be an ignition source for combustible or flammable compounds (such as gases, vapors, dust, fibers, and more). Click here to view all our HazLoc rated analyzers.

Operating Conditions

  • Temperature 0°C – 40°C (Extended ranges optional)
  • Humidity 0-100%

How it Works

Overview

The Cerex UV Sentry operates using a technique known as UV-DOAS (Ultra Violet Differential Optical Absorption Spectroscopy). A beam of UV light is sent from the UV Sentry through the open air to a retroreflector array up to 1300 meters away; the light is then reflected by the retroreflector array and returns to the UV Sentry. This process is known as open-path monitoring: measuring compounds within the air via a beam of light.

Setup & Installation

The UV Sentry mounts to a precision pan and tilt head which may be used with a tripod for rapid deployment, or with a fixed mount for permanent installations. The retro-reflector array is housed in a protective enclosure and may be tripod or fixed mounted to a mast, pole or superstructure.

Benefits

 

Combining the UV-DOAS technique with parts per trillion to parts per billion detection limits makes the Cerex UV Sentry one of the most affordable and accurate solutions for perimeter & fenceline monitoring. Dozens of gases and compounds can be monitored within the UV light spectrum, notably Benzene and Chlorine, for a valuable low-cost solution.


(Above) Process of open-path monitoring (depicted with a Cerex UV Sentry). The Cerex UV Sentry mounts to a precision pan and tilt head which may be used with a tripod for rapid deployment, or with a fixed mount for permanent installations. The retro-reflector array is housed in a NEMA enclosure and may be tripod or fixed mounted to a mast, pole or superstructure. Monitoring path lengths are typically configured to meet minimum detection limits required for the project. Paths to 1 km are possible. Gases present in the beam path are identified and quantified in near real time. Credit: STI

Common Detectable Gases

Common Detectable Gases

Dozens of compounds can be targeted with a UV-DOAS configured library. Combined with Cerex’s real-time analysis software, up to 50 compounds can be monitored simultaneously. Each Cerex UV-DOAS analyzer includes free setup of a custom-tailored library that best fits your application.

The UV Sentry has as low as parts per trillion to parts per billion minimum detection limits and wide dynamic ranges, allowing earlier and more thorough detection of gases than traditional sensor arrays.

 

UV Sentry Common Target Gases

Common Detectable Gases

UV Sentry Common Target Gases

Acetaldehyde

Acrolein

Ammonia

Benzene

1,3-Butadiene

Carbon Disulfide

Chlorine

Chlorine Dioxide

Ethylbenzene

Formaldehyde

Hydrogen Sulfide

Naphthalene

Nitric Oxide

Nitrogen Dioxide

Ozone

Phenol

Styrene

Sulfur Dioxide

Toluene

m-, o-, p-Xylenes

See full UV-DOAS Gas Library

*NOTE: For detection of gaseous compounds not available within the UV spectrum, we recommend the Cerex AIR SENTRY – an open-path analyzer that uses FTIR (Fourier Transform Infrared). Find more information about UV-DOAS and FTIR techniques here.

Software


Real time spectral subtraction and synthetic background implementation allow the UV Sentry to clearly display accurate concentrations of target gases over 1000 meters without interference from other gas species

Results You Can Rely On

Cerex recognizes that detailed gas monitoring results need to be reliable and available quickly to various stakeholders. For this reason, Cerex engineers developed software to accurately detect and display gases within the air in real time from any location.

A user can see results in numerous ways: on-site via a touchscreen computer that is included on every analyzer, or remotely on a phone, tablet, or computer anywhere in the world via a virtual connection. GPS and cellular configurations make this possible in remote environments.

All data is automatically saved in an easy to access .csv file; this feature helps our clients in various ways - from daily use to crucial events such as evidence in court.

Learn more about the benefits of our proprietary analysis software here.

The most cost effective perimeter & fenceline monitoring solution…

Multi-gas monitoring over linear distances exceeding 1000 meters, minimal infrastructure requirements and direct integration with existing factory management systems provide cost effective installation. Low consumables, field proven service life, inherent calibration and “hands off” operation provide low cost of ownership.

Offers parts per trillion real time detection limits for early warning of fugitive emissions…

Parts per trillion to low parts per billion detection limits and wide dynamic ranges enhance early leak detection and release characterization. Concentrations of gases below the detection thresholds of traditional sensor arrays are readily detectable with the UV Sentry analyzer. Early detection translates into quicker response times, reduced environmental impact, decreased plant downtime and reduced exposure of site personnel and the community.

Of individual species of prolific hazardous air pollutants…

UV Sentry analyzers quantify individual species of toxic gases within complex mixtures using standard CLS analysis coupled with proprietary real time spectral analysis routines. Monitoring performance is immune to interference from water vapor and the UV Sentry analyzer cannot be poisoned. Typical accuracy and precision at FAT are 2.5% and 3.0% of reading respectively.

Species include gases commonly of concern in Chemical Manufacturing, Refinery Operations, Acid Plant Operations and Ore Processing, Concrete Manufacturing, Mining Operations, Environmental Remediation and More…

Applications

EPA 40 CFR 63.658, BAAQMD Rule 12-15 and SCAQMD Rule 1180 Compliance

With part per trillion minimum detection limits for Benzene, the UV Sentry allows regulatory compliance for SCAQMD Rule 1180 and BAAQMD Rule 12-15 BTEX monitoring. It also represents a stand-alone solution for alternative MACT compliance for US EPA Method 325 refinery fence-line benzene monitoring.

As a stand alone analyzer for BTEX, Acrolein, Formaldehyde, SO2, Styrene… or as a component within a larger analyzer array including the Cerex AirSentry FTIR for Ammonia, Alkanes, Formaldehyde, HF, HCN, etc… Cerex offers comprehensive monitoring compliance solutions for Federal, State and Regional monitoring requirements.

(PDF 1.4MB) Download US EPA, BAAQMD and SCAQMD Refinery Compliance Solutions


See client examples of the UV Sentry in action

All Applications

  • Acid Plant Monitoring
  • Benzene, Toluene, and Xylenes (BTEX)
  • Brownfield Remediation
  • Chemical Depot Monitoring
  • Electrowinning Emissions Monitoring
  • Fence-line Monitoring System (FLMS)
  • Manufactured Gas Plant Remediation (MGP)
  • Perimeter Ambient Monitoring System (PAMS)
  • Superfund Site Remediation
  • Tank Farm Monitoring
  • Regulation Compliance
    • EPA Method 325
    • 40 CFR 63.658 (MACT)
    • SCAQMD Rule 1180
    • BAAQMD Rule 12-15

UV Sentry Specifications

Bulb Options
Deuterium Xenon
Monitoring fence-line lengths up to 225m mono-static or 450m bi-static Monitoring fence-line lengths in excess of 1000m
UV400 or better eye
protection required.
Guaranteed 2000 hour
lamp half-life
-- Easier to align at longer distances due to the high visible component of light

 

Detectable Compounds

Deuterium Xenon
1,3-Butadiene (C4H6)
Acetaldehyde (C2H4O)
Ammonia (NH3)
Benzaldehyde (C7H6O)
Benzene (C6H6)
Benzyl Chloride (C6H5CH2Cl)
Carbon Disulfide (CS2)
Chlorine (Cl2)
Chlorine Dioxide (ClO2)
Ethylbenzene (C8H10)
Flourine (F2)
Formaldehyde (CH2O)
Glutaraldehyde (CH2(CH2CHO)2)
Isoprene (C5H8)
Mercury (Hg)
Naphthalene (C10H8)
Nitric Oxide (NO)
Nitrogen Dioxide (NO2)
Nitrous Acid (HNO2)
Ozone (O3)
Phenol (C6H5OH)
Propionaldehyde (CH3CH2CHO)
Styrene (C8H8)
Sulfur Dioxide (SO2) - high sensitivity
Toluene (C6H5CH3)
Trimethylbenzene (C9H12)
Valeraldehyde (C5H10O)
m-Xylene (C8H10)
o-Xylene (C8H10)
p-Xylene (C8H10)
Acetaldehyde (C2H4O)
Acrolein (C3H4O)
Benzaldehyde (C7H6O)
Benzene (C6H6)
Benzyl Chloride (C6H5CH2Cl)
Carbon Disulfide (CS2)
Chlorine (Cl2)
Chlorine Dioxide (ClO2)
Ethylbenzene (C8H10)
Flourine (F2)
Formaldehyde (CH2O)
Glutaraldehyde (CH2(CH2CHO)2)
Isoprene (C5H8)
Mercury (Hg)
Naphthalene (C10H8)
Nitrogen Dioxide (NO2)
Nitrous Acid (HNO2)
Ozone (O3)
Phenol (C6H5OH)
Propionaldehyde (CH3CH2CHO)
Styrene (C8H8)
Sulfur Dioxide (SO2)
Toluene (C6H5CH3)
Trimethylbenzene (C9H12)
Valeraldehyde (C5H10O)
m-Xylene (C8H10)
o-Xylene (C8H10)
p-Xylene (C8H10)
General Parameters
Part Number UV Sentry-XX-YY-ZZ
XX = XE for Xenon or D2 for Deuterium
YY = Blank for standard enclosure or SS for sealed enclosure
ZZ = Blank for standard monostatic configuration or TX for bistatic transmitter and RX for bistatic receiver
Analyzer Type Multi-gas open path analyzer convertible to multi-gas point analyzer.
Technology UltraViolet Differential Optical Absorption Spectroscopy (UV-DOAS)
Performance Standard configuration is up to 5 compounds; capable of simultaneous analysis of up to 25 compounds
Data Output Rate User selectable from 5 seconds and up
Typical output rates are 30s, 60s, 120s, or 300s
Time weighted average available for user defined periods (8 hour, 12 hour, 24 hour)
Measurement Principle Beer-Lambert Law
Measurement Technique Classical Least Squares (CLS) regression analysis; optional Partial Least Squares (PLS)
Maximum Open Path Installation Distance Gas species/mixture dependent - optical power capable to exceed 1000 meters linear separation
Operating Temperature 0°C to 50°C (Air Cooled Model), -40° to 55°C (Optional TE AC Cooled)
Storage Temperature -40C° to 60C°
Power Supply 100 to 130V or 200 to 240VAC/50-60Hz
Power Consumption 700W max (standard model)
1400W max (sealed TE cooled model)
Instrument Cooling Air cooled (optional TE air conditioner)
Alignment Mechanism Heavy duty gear driven pan and tilt head (PN 282264) or intelligent automated motorized positioner
Installation Fixed mount or tripod mount
Dimensions (standard model with rain hoods) 33.4" x 15.2" x 16.4" (85cm x 38.6cm x 41.7cm)
Dimensions (standard model without rain hoods - sheltered installation) 25" x 15.2" x 16.4" (63.5cm x 38.6cm x 41.7cm)
Weight (standard model) 53 lbs (24Kg)
Dimensions (sealed model with rain hoods) 32.2" x 22.8" x 18.4" (81.7cm x 58cm x 46.6cm)
Measuring Parameters
Concentration measurement accuracy ±5 % Reading TYP
Concentration measurement precision ±5 % Reading TYP
Interferent Mitigation Real time spectral subtraction and residual subtraction, multi-peak analysis.
Zero point calibration Simultaneous dual mode natural zero and/or synthetic zero on gas by gas basis. Automated compound specific background selection.
Software
Real Time Operating Software Cerex Continuous Monitoring Software (CMS)
Operating System Windows 7, 8, 10
Post Collection Analysis Software Cerex Data Processor
Operating System Windows 7, 8, 10
Spectrometer
Scan frequency 8-500mS
Detector Back-thinned CCD
Source 35W Deuterium or 100W Xenon
Wavelength range 200-400nm typical
Internal Quality Assurance Cell
Type Internal linear multi-pass cell permanently mounted in beam path. External window removable.
Calibration gas inlet 1/4" Swagelok
Calibration gas outlet 3/8" Swagelok
Path Length 0.047m
Volume 0.33 L
Maximum sample pressure 1 PSI
Pressure and temperature measurement Integrated pressure and temperature sensor
Integration
HMI Touchscreen (standard model)
Digital Interface RJ45 Ethernet LAN Port for local or internet based remote data and access using MODBUS TCP, VNC, and remote desktop.  Spectral data may be stored locally, on a NAS, or disabled. Industrial external wireless option available. Type A USB for data retrieval and peripheral accessories.
Power Connection Environmentally sealed circular Amphenol bayonet connector.
Integrated Computer Embedded industrial PC.
Options
Automated Motorized Positioner Intelligent automatic multi-path positioner: Operator programmable path scanning or dynamic path scanning based on meterological conditions.
Integrated Wind Mapping Three dimesnional ultrasonic anemometer with temperature measurement. Data integrated into CMS data tables and available via MODBUS.
Integrated Data Acqusition External ports with data integration for particulate or ancillary co-located analyzers (TDLAS laser, electrochemical, etc.).
Data Output MODBUS over RS-232, RS-485.  MODBUS over TCP-IP is standard.
Analog Output 8 channel configurable 0-24mA (4-20mA with extended range)

Downloads (PDFs)

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