- Model 4500 MkIII - Compliance Opacity and Dust Monitor



The Land Model 4500 MkIII has reset the industry standard on compliance opacity and dust concentration measurement. Combining the unique features of three patented technologies, the 4500 MkIII achieves the highest available specification for the principal performance parameters, as defined by the internationally recognized ASTM Standard D 6216-07.


The 4500 MkIII complies with:

  • EN 15267-1:2009
  • EN 15267 - 2 :2009
  • EN 15267 - 3 :2007
  • EN 14181  :2004
  • EN 15267-3 tested
  • QAL 1 Certified
  • TUV approved
  • Annual Inspection

The Land Model 4500 MkIII has reset the industry standard on compliance opacity and dust concentration measurement. Combining the unique features of three patented technologies, the 4500 MkIII achieves the highest available specification for the principal performance parameters, as defined by the internationally recognized ASTM Standard B 6216. These industry-leading features makes the 4500 MkIII the most accurate opacity monitor available today. Its excellent sensitivity makes it ideal for all current or future requirements in opacity and dust concentration measurement.

Combining the unique features of three patented technologies, the 4500MkIII achieves the highest possible specification for the fundamental performance parameters for a compliance opacity monitor, as defined by the internationally-recognized ASTM Standard D6216. Its performance has been independently verified, meeting the QAL 1 requirements for EN 13284-2 and EN 15267-3.

Performance Specifications

  • US EPA 40CFR60, Appendix B Performance Standard and Procedure 3
  • ASTM D6216-07 and D6216-12
  • QAL 1


  • EN 15267 - 1
  • EN 15267 - 2
  • EN 15267 - 3
  • EN 13284 - 2

Industrial Applications

  • Boilers
  • Heaters
  • Furnaces
  • Kilns
  • FCC’s
  • Incinerators
  • Dust Collectors

Measuring System

  • Technique: Cross stack, double pass / path transmissometry
  • Operating Wavelength: 520 ±20 nm
  • Light Source: High Intensity LED
  • Range:
    • Opacity 0 - 10 % to 0 - 100 %
    • Optical Density 0 - 0.1 to 0 - 3.0
    • Dust Density 0 - 10 to 0 - 10 000 mg/m3
    • User Selectable
  • Calibration Error: ± 1.5 % Opacity
  • Drift (long term): < 0.3 % Opacity / month
  • Resolution: 0.1% Opacity; 0.001 Optical Density; 0.1mg/m³ Dust
  • Angle of projection: 3°
  • Anglle of view: 3°
  • Installation pathlength: 0.5 to 10 m / 20 in to 32 ft
  • Calibration: Automatic Zero and upscale calibration, Selectable period 1 to 24 hours in 1 hour steps
  • Zero Correction: Automatic correction for zero drift
  • Response Time:    < 10s, (< 2s with no damping)
  • Averaging: Selectable from 10 s to 24 hr (1 s increments)

ASTM Standard

  • Calibration Error per ASTM D6216: < 1.5% Opacity
  • 24 Hour Drift: < 0.3% Opacity
  • Long Term Drift: < 0.3% Opacity per month
  • Voltage Variation per ASTM D6216: < 0.2% Opacity (over 85 - 265 V a.c.)
  • Thermal Stability per ASTM D6216: < 0.6% Opacity (over -20 to +55°C / -4 to +131°F range)
  • Ambient Light Sensitivity per ASTM D6216: < 0.2% Opacity
  • Insensitivity to misalignment: < 1% Opacity for ±0.25° misalignment

Control Panel

  • Display: 128 x 64 pixel reflective backlit LCD
  • Keypad: 4 keys for data input
  • Indicators: Power, System OK, Alarm, Calibration


  • Operating Temperature: -40 to +55 °C / -40°F to +131 °F
  • Max Flue Gas Temp.: 600 °C / 1112 °F
  • Max Flange Temp.: 200 °C / 392 °F


  • Modbus Interface: RS485. Opacity, Optical Density, Dust Density
  • and Status information available
  • Analogue outputs: Isolated 4 to 20 mA Configurable as Opacity,
  • Optical Density, Dust Density
  • Relay outputs: System OK, Calibration, Alarm
  • Relay rating: 1 A @ 24 Vdc


  • Power Supply: 24 Vdc nominal (18 to 30 Vdc)
  • Current Consumption: 0.3 A nominal (3 A startup)

Mechanical Data

  • Transceiver: (HxWxD) 191 x 201 x 413 mm / 7.5 x 7.9 x 16.3 in
  • Retro-reflector: (HxWxD) 191 x 201 x 237 mm / 7.5 x 7.9 x 9.3 in
  • Weight Transceiver: 6 kg / 13.2 lbs
  • Weight Retro-reflector: 3 kg / 6.6 lbs


  • Transceiver / Retro-reflector: Cast Aluminum, epoxy coated

Optional Accessories

  • Air Blower units
  • Automatic Fail-Safe Shutters
  • Weather Covers
  • Remote Control Room Unit
  • Adaptor Flanges
  • Additional outputs available

Approvals: EN15267-1, EN15267-2, EN15267-3, EN13284-2
Performance Specifications: QAL1, US EPA PS-1, ASTM D6216, US EPA Procedure 3

Compliance Applications

  • US EPA 40CFR60 Sections 13, 17 and App. B PS-1
  • US EPA Proposed 40CFR60 App. F Procedure 3
  • ASTM Standard D6216
  • EN 15267-1:2009
  • EN 15267 - 2 :2009
  • EN 15267 - 3 :2007
  • EN 14181  :2004

Industrial Applications

  • Boilers
  • Heaters
  • Furnaces
  • Kilns
  • FCC’s
  • Incinerators 
  • Dust Collectors


Control Room Unit

The Control Room Unit (CRU) provides a direct link for the operator to see at a glance the instrument readings, display warning or alarm conditions and provide a range of options including analog and digital outputs. In addition, an instrument calibration can be initiated by remote control.
The unit is simple to install and connect to the opacity monitor,using the termination box.


  • Live Information Direct from the Opacity Monitor into the Control Room or other convenient location
  • Available as 19”rack-mount configuration, includes mains power-supply
  • Uses Modbus RS 485, 2 Wire Connection to Opacity Monitor
  • Display of Instantaneous and Average Opacity, Optical Density and Dust Readings
  • 10 day Data Log available for PC download
  • Remote Calibration Initiate Function
  • Display of Instrument Warnings and Alarms
  • Calibration Status Indication
  • Optional Input/Output Module -providing 4 Analog O/Ps, 1 Digital I/Pand 15 Relay O/Ps
  • Also available for Model 9100 CO monitor


AFU & APS (optional)

The Auxiliary Functions Unit and Auxiliary Power Supply Supply (AFU/APS) provides additional communications and control facilities for the Model 4500 MkIII:

  • 2 isolated 4 - 20 mA current loop outputs
  • 2 alarm relays
  • 4 status and calibration relays
  • 4 blower status inputs
  • 4 fail-safe shutter status inputs
  • 2 fail-safe shutter control outputs
  • 4-wire Modbus port
  • RS232 or RS485 diagnostic port
  • 110 v or 230 V ac mains power supply
  • Circuit breakers and terminals for ac supply distribution

The AFU/APS connects to the Transceiver via its RS485 Modbus port.

If the AFU/APS is used to provide connections to Blowers and Fail-safe shutters, it must be located close to the 4500 MkIII Transceiver.


Air Purge Blowers

The plate-mounted blower unit is designed for vertical mounting to a stack or duct, and is available with two sizesof fan unit, to accommodate different stack pressures and instrument types.

It is suitable for either indoor or outdoor installation. An optional weatherproof cover is available for exposed locations.


Fail-safe Shutters

A signal-operated shutter unit is available for these instruments. It may be prudent to fit shutters to protect the instrument if the blower fails. These are particularly important for applications where flue gas is under positive pressure, and/or where it is very corrosive. If the air purge supply fails (normally due to mains power failure), the instrument should be removed to avoid permanent damage. With positive seal, fail-safe shutters, the instrument can normally be left in place  until the air purging is restored.

When does the shutter operate?

Shutters operate in certain conditions and depending on whether the air purge supply (normally a blower) has pressure switches fitted. The shutters will automatically re-open when the fault condition is rectified, i.e. mains power is restored or the pressure switches change state - no user intervention is required. The shutter mechanism will operate once (close and re-open) during a calibration cycle (4500 Series), in order to check that it is operating correctly. The instrument’s software will automatically trigger this operation.


External Zero Device (EZD)

The EZD allows you to verify the zero opacity point without removing the Model 4500 MkIII from the stack. It can also be used for quarterly calibration error checks, as required by US EPA Procedure 3.

Neutral Density Calibration Filters

Filters are chosen to match your opacity monitor configuration and are calibrated as primary filters in accordance with PS-1.


Transceiver Weather covers

To be used when additional environmental protection is required. It simply hooks over the instrument, to protect from sunlight and rain. It hinges upwards for access to the instrument itself.


Calibration Stands

A set of calibration stands are important when performing a Clear Stack Calibration or Zero alignment. The instrument (to comply with US EPA Procedure 3), must be removed and attached to test stands for calibration.




The standpipe welds directly to the stack for a simple, rigid mounting.


Spoolpieces are available with a wide variety of ANSI Flange sizes which can be bolted onto an existing stack flange.

  • Lifetime warranty on LED light source
  • 3-year warranty on transmissometer
  • No continuously moving parts
  • Patented all-glass multi-prism retroreflector
  • Patented flood LED
  • Optional fail-safe shutters
  • Adaptor flanges and spoolpieces
  • Control Room Unit (option)
  • Single Purge Blower
  • Wide operating temperature range
  • Auxiliary Function Unit (AFU)
  • Auxiliary Power Supply (APS)

  • No need to replace the light source
  • Worry-free operation
  • Highest reliability
  • Lowest possible drift
  • Maximum thermal stability
  • Protects optics if purge air fails, and protects personnel from stack
  • gases during servicing
  • Allows the 4500 MkIII to fit the existing stack flanges
  • Allows remote display and diagnostics
  • One blower provides purge air to transceiver and retro
  • Operation -40°C to 55°C (-40°F to 131°F) is standard
  • Easy connections and additional I/O
  • Universal mains power input and power distribution

Customer reviews

No reviews were found for Land - Model 4500 MkIII - Compliance Opacity and Dust Monitor. Be the first to review!