Apogee SQ-100 Series User manual

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Quantum
Sensor
Owners Manual
Model: SQ-100,
200 & 300
Series
Specifications
Calibration
Quantum sensors are calibrated for electric light or
sunlight. Averagespectralerrors associated with each
calibration are shown below.
435-792-4700
www.apogeeinstruments.com
[e-mail]
Setup Instructions
1. Attach thesensor toa meter or datalogger that
can display or record a mV output.
The sensor is self-powered.
Themodel, serialnumber, production date, and
calibration factor are located on thesensor cable.
Electric
Calibration
Sunlight
Calibration
Cool
White
Fluorescent
0% error 8% high
MetalHalide 2% low 6% high
High Pressure
Sodium 8% low 0% error
Sunlight 8% low0% error
Application Measuring Photosynthetic Photon Flux
Output Responsivity0.200 mV per µmol m-2 s-1
In full sunlight 400 mV (2000 μmol m-2 s-1)
Linearrange 1000 mV (5000 μmol m-2 s-1)
Sensitivity Calibrated toexactly 5.00 µmol m-2 s-1 per mV
Input power None, self-powered
Operating environment -40to55 °C; 0to100% relativehumidity. Designed
for continuousoutdoor use. Can besubmerged
underwater (with or without mounting screw).
Materials Anodized aluminum with acrylic lens
Cable 3 meters of shielded, twisted-pair wire with
Santoprenecasing,ending in pigtail leads.
Additionalcable $1.95/meter.
Dimensions 2.4 cm diameter, 2.75 cm high
Mass 70 g: SQ-313& 323, 240 g: SQ-316& 326,
400 g: SQ-311 & 321
Warranty 1yearagainstdefects inmaterials/workmanship
Red: positive (signal
fromsensor)
Black: negative
(signal fromsensor)
Clear: shield/ground
DO NOT attach the sensor
to any power source
SQ-120 4860
29 FEB 2008
5.00

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Quantum Sensor Models
A quantum refers totheamount of energycarried
bya photon. Apogee quantum sensors approximate
thequantityof photonsbetween 400 and700
nanometers. Photosynthesis is largely driven by
thenumber of photonsbetween these wavelengths,
so this radiation is called thePhotosynthetic Photon
Flux (PPF) andis measured in μmol m-2 s-1.
Cosine response
Someof theradiation coming intoa sensor at low angles is reflected, which
causes low readings. Theconvex opticaldisc is designed tocapture radiation
at low angles andminimizecosineresponse errors. Thecosineerror for
typicalapplicationsis less than 2%.
Temperature response
Thetemperature response is less than 0.1% per degree Celsius. This
temperature error is not significant in most applications.
Long-term stability
Ourresearch indicates that theoutput increases approximately 1% per year
because of changes in theopticaltransparencyof thediffusion disk. We
recommendreturning thesensor for recalibration every 2years.
Spectral Response
Asshown in thegraph below,quantum response bydefinition is from 400 to
700 nm,andgives equalemphasis toall photonsin that range. Thespectral
response of theApogee sensor, aswell asa typicalplant response, are also
shown.
Quantum Sensors
Calibrated for electric light
SQ-120
Calibrated for sun light
SQ-110
Line Quantum Sensors
3PECIFYCALIBRATIONFORSUNLIGHTORELECTRICLIGHTDIFFERENCE
3 sensors, 50cm length; SQ-313 (Sun),SQ-323 (Electric)
6 sensors, 50cm length; 316 (Sun),SQ-326 (Electric)
10 sensors, 70cm length; SQ-311 (Sun),SQ-321 (Electric)
US Patent No. D519,860
Full Sunlight
(2000 μmol m s)
Sensor Output
(400 mV)
PPF = sensor output x conversion factor
400 mV x 5.00μmol m-2 s
-1
= 2,000 μmol m-2 s-1
Calibration
All quantum sensor models have a stan-
dard calibration of exactly:
5.00 μmol m-2 s-1 per mV
Use theconversion factor
(5.00 μmol m
-2 s-1 per mV) to
convert themV signalfrom the
sensor tophotosynthetic photon
flux in μmol m
-2 s-1 (multiply the
mV output bytheconversion
factor toyield μmol m-2 s-1).
Each sensor is equipped
with a mounting bolt.
Mount thesensor as
level aspossible. Small
changes in level can cause
measurement errors. We
recommendusing our
leveling plate(model AL-100)
for themost accurate
measurements. Thesensor
should bemounted with the
cable pointing toward the
nearest magnetic pole to
minimizeazimuth error.
N
S
N
N
Model AL-100
Bolt: 10-32x5/8
Mounting the Sensor
Orientation
Apogee Quantum
Response