Opacity & Dust Concentration Monitor

D-R 290

The transceiver emits a beam of light that passes through the stack or duct and strikes a refl ector. The light beam is refl ected back and the amount of light returned is measured by the transceiver. Dust particles in the stack will absorb and scatter the transmitted beam of light so that the returned light will be less than the transmitted light. The ratio of the returned light is called the transmission. One (1) minus the transmission is referred to as the opacity. For dust concentration measurements, optical density (also called extinction), is historically used because of the linear relationship between dust concentration and optical density. The of one (1) divided by the transmission yields the optical density. The measured transmission value is sent via RS 422 to the stack display, the measured value can be read and maintenance actions initiated. Purge air alarms are also wired to this stack display. The measured values and any purge air sys-tem faults are then sent via RS 422 to the D-R 290 AW remote display.

At the remote display, the measured value is displayed and the system parameters can be viewed or changed. This remote display also contains the system status inputs, the relay outputs and the two independent current outputs. One current output may be set to read opacity and the other to read dust concentration. If dust concentration is required, a stack test is normally required to calibrate the extinction reading to a specifi c concentration (e.g. determine the extinction coeffi cient). Purge air blowers are used to keep the optics clean. Weather hoods are used to protect the blowers and the monitor from the environment. Fail-safe shutters can be installed to protect the optics if a purge air blower should fail or lose power and may also protect service personnel on over-pressure stacks. These shutters are exercised during the daily calibration to insure they are in working order when needed and to prevent them from sticking in the open position.

In situ, double-pass measuring principle for continuous opacity monitoring Long-life, solid state light source High performance microprocessor technology Liquid crystal display in opacity or optical density, calibration capability in mg/m3 or gr/dscf Automatic zero and span check with correction for window contamination Optics and electronics in a hermetically sealed housing Simple alignment without special tools Reduced maintenance due to advanced purge air system Programming via the remote display unit Adapter fl anges available to replace existing opacity systems Fiber optic communication capability

SYSTEM FEATURES

DESCRIPTION

Meets and exceeds PS1 & ATSM Standards

Innovative Solutions for YourCombustion and Emission Needs

1355 Mendota Heights Road, Ste. #200Mendota Heights, MN 55120 USA

Tel: +1.451.1710 Fax: +1 651.457.7684

Comparison Normal Zero Point Control Refl ector

Heated Exit Window

Refl ector

Stack

SWBDSuper Wide Band Diode

Focus Adjustment

Alignment Indicator

Photodetector

D-R 290 Technical Specifi cationsLight Source ........................................White Super Wide Band DiodeSpecial Response ............................................................ Peak: 50 nm........................................................................................Mean 560 nmAngle of View .................................................................................< 4°Angle of Projection ........................................................................< 4°Response Time ................................................................ < 8 seconds

Measuring RangeOpacity ............................................................ From 20% up to 100%Optical Density ................................................ From 0.1 up to 1.6 Ext.Dust Concentration (1 m path) ............. 0-200 mg/m3 to 0-400 mg/m3Length of the measuring path .................................. 1-45 ft (0.5-45 m)Output Signal ............................................. Two independent 4-20 mAMaximum Load .................................................................... 500 ohmsRelay Outputs ...................................... Six dry contacts: for limit value............................................................................ calibration cycle, etc.Maximum Switching Capacity ........................................ 250 V 100 VAInputs ................................................................... Calibration functionsOutput Signal Integration Time ..........5-1800 seconds, programmable

Temperature RangesAmbient Temperature ..................... -40°F to 122°F (-40°C to +50°C)Flue Gas Temperature ................................................ Above dewpoint

Electrical Specifi cationPower Supply ......................................................90 - 264 V, 48-62 HzPower Consumption ............................................ Approximately 30 W

Mechanical DataEnclosure Rating ...................................................... NEMA 4X (IP 65)Weight ..................................................................... Transceiver: 22lb..................................................................................... Refl ector: 15 lb.

Purge Air AssemblyPower Supply .......................................................... 115/230V, 1/2 HPBlower Output ............................................................................50 cfmMeasurement (weather hoods) ..................................... 21” x 30” x 36”Weight ........................................................................................ 75 lb.

▪ Mounting Flanges▪ Measuring Head▪ Refl ector▪ Remote Display and Operating Panel▪ Two Purge Air Bowers▪ Protective Weather Hoods▪ Local Stack Display

Scope of Delivery Optional Accessories▪ Automatic Fail-Safe Shutters▪ Explosion-Proof Model▪ Fiber Optic Communication▪ Remote Display and Operating Panel