2 Wavelength
Integrating Nephelometer
The Ambilabs dual wavelength nephelometer is a robust ambient airquality instrument designed to provide measurements of
particle concentrations, ambient visibility, and source apportionment
information. The unit includes an LCD display to provide information
about measured parameters, flow rate, instrument status and power. An
active heating system which is controlled based on relative humidity
levels warms the sample air and sample cell to keep the RH below a set
point to avoid particle growth with humidity. Additional features
include a purge air system and an automatic zero calibration
routine. The instrument can be installed in any ambient shelter or
monitoring facility. The Ambilabs dual wavelength nephelometer
determines particulate concentration by measuring the total scatter from
aerosols using a selectable wavelength, while both wavelengths are used
to determine the scattering Ångström exponent which is inversely
related to particle size in the sample air, showing basically the average
(mode) diameter of the measured particle size distribution. While the
time series of the scattering coefficient already represents the measured
particle concentration, the Ambilabs dual wavelength nephelometer has
a separate output for a PMestimate based on a user selectable calibration
with measurement range of 0 to 100 mg/cubic meter or 0 to 100,000 ug/
cubic meter. Optional sharp-cut cyclones can be used to select the
sample flow for PM1, PM2.5, or PM10 size fractions.
BENEFITS:
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Example of Ångström Exponent Usage (above):
On 6/23/15, the Ångström Exponent (green) decreases, revealing the coarse particle
influence from a Sahara Dust event in Atlanta, GA. Collocated PM measurements show a
corresponding increase in PM10 concentration (yellow). The red scattering coefficient
(635 nm) follows mostly the PM2.5 concentration and can be scaled with a user defined
factor to get a PM2.5 estimate. The 1 minute Nephelometer data show the exceptional time
resolution of the instrument. The noise level for 1 minute values is smaller than the noise
level of the hourly PM measurements (FEM particulate comparison monitor), indicating
the outstanding precision of the nephelometer. NOTE: Instrument also performs
automated, internal quality control via a built-in zero check feature every 24 hours (as
represented in the above graph).
[email protected] (401) 247-0100
Easy automatic calibration with cost effective (low
grade) CO2 gas ensures repeatability of measurement
Automatic optical reference calibration
High powered LED light source increases
measurement accuracy
Single light source and detector used for all
wavelengths
Facilitates a wide measuring range (0 to 20,000
Mm⁻¹)
Compact and portable
QA parameters available like “cleaning
indicator” (wall count) and “lamp intesity
drift” (shutter count)
Internal sample heater with temperature or RH
control, which can be enabled by the user to
eliminates effects of humidity RH: <30% to <90%
Fully automatic zero check or adjust, automatic
span check or automatic zero and span check
available in intervals of 1, 3, 6, 12, 24 hours or
weekly
Fully integrated package including: internal sample
pump, sample heater, internal calibration valves,
zero air pump, and data logger
Low power internal 12V sample heater
Long lasting LED light source
Very low cost of ownership
SPECIFICATIONS:
Measured Parameters:
Ranges:
Lower Detectable Limit:
Secondary Measurements:
Intensity Function:
Flow Rate:
Operating Temperature:
Operating RH:
Calibration:
Optics:
Light Source:
Wavelength:
Operating Voltage:
Dimensions:
Weight:
Light scattering coefficient (σSP) at 2 user selectable wavelengths from built-in 3 wavelength
light source (450, 525, and 635 nm)
0.0 to >20,000Mmˉ¹
<0.3Mmˉ¹ (60 second averaged data)
Sample air temperature, chassis temperature, relative humidity, and sample pressure
Full scatter 9-170°
5 l/min nominal (not controlled)
-20 to 45°C
10 to 95%
Span gas selection and calibration values for CO2, SF6, FM-200, R-12, R-134, or a user
defined gas
Reference brightness shutter
Stable LED light source
525nm (green), 450nm (blue), and 635nm (red) [only 2 can be operated at one time]
12 VDC (including 110-240 VAC 50/60 Hz power converter) [60 watts with heater active]
6.7” x 27.5” x 8.5” (L x W x H)
24.7 lbs.
COMMUNICATIONS/
DATA LOGGING:
Outputs:
Filtering:
Stored Parameters:
Capacity:
4 analog outputs (2 voltage and 2 current) and 2 x RS232 serial ports
Kalman (digital adaptive filter), moving average (30 seconds), or no filter
Date and time, 2 x σSP (635, 525, or 450 selectable), PMestimate, Ångström exponent, air temp,
enclosure temp, RH, pressure, status
At least 33 days of 5 minute averages, or 6 days of 1 minute averaged data
OPTIONS:
APPLICATIONS:
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External pump control
Naphion Dryer inlet to avoid
losses of volatile particles
Solar power panels and
batteries
Roof flange kit and rain cap
with insect screen
Gas calibration kit and wall
mount bracket
Measurements of light scattering
Air Quality Index/PMestimate
Source apportionment
Ångström exponent calculations
Smoke monitoring
Ambient dust monitoring
Industrial process measurements
Clean rooms
[email protected] (401) 247-0100