Apogee Instruments SU-202 Owner'S Manual Download Page 16

Unit Conversion 

SU-200 series UV-A sensors are calibrated in energy flux units of W m

-2

. It is possible to convert the energy flux 

value to photon flux units of µmol m

-2

 s

-1

 using a conversion factor. Below is an example of how to convert energy 

flux units to photon flux. 

1)

 

Calculate the sensor output in units of J m

-2

 s

-1

6 𝑚𝑉 ∗ 10 

𝑊𝑚

−2

𝑚𝑉

= 60

𝑊

𝑚

2

= 60

𝐽

𝑚

2

𝑠

 

 

2)

 

Multiply the energy flux units by the conversion factor. It’s important to note that each light source needs 
a specific conversion factor. The conversion factor used in the example equation is the sunlight 
conversion factor.s 

60 

𝐽

𝑚

2

𝑠

∗ 0.327

𝜇𝑚𝑜𝑙

𝐽

= 19.62

𝜇𝑚𝑜𝑙

𝑚

2

𝑠

 

 

Summary of Contents for SU-202

Page 1: ...NC 721 WEST 1800 NORTH LOGAN UTAH 84321 USA TEL 435 792 4700 FAX 435 787 8268 WEB APOGEEINSTRUMENTS COM Copyright 2020 Apogee Instruments Inc OWNER S MANUAL ULTRAVIOLET A SENSOR Models SU 202 and SU 205 including SS models ...

Page 2: ...e of Compliance 3 Introduction 4 Sensor Models 5 Specifications 6 Deployment and Installation 9 Cable Connectors 10 Operation and Measurement 11 Maintenance and Recalibration 14 Troubleshooting and Customer Support 15 Return and Warranty Policy 17 ...

Page 3: ... of electrical and electronic products with respect to the restriction of hazardous substances Please be advised that based on the information available to us from our raw material suppliers the products manufactured by us do not contain as intentional additives any of the restricted materials including lead see note below mercury cadmium hexavalent chromium polybrominated biphenyls PBB polybromin...

Page 4: ...to Joules per second per square meter The output can also be expressed in photon flux density units of micromoles per square meter per second µmol m 2 s 1 Typical applications of UV sensors include incoming UV radiation measurement in outdoor environments or in laboratory use with artificial light sources e g germicidal lamps Apogee Instruments SU 200 series UV A sensors consist of a cast acrylic ...

Page 5: ...date of your sensor please contact Apogee Instruments with the serial number of your sensor SENSOR MODELS This manual covers the amplified model SU 202 and SU 205 UV A sensors listed below in bold Additional models are covered in their respective manuals Model Signal SU 200 0 10 mV SU 202 0 2 5 V SU 205 0 5 V ...

Page 6: ...bration Factor reciprocal of sensitivity 0 04 W m 2 per mV 0 12 µmol m s per mV 0 02 W m 2 per mV 0 06 µmol m s per mV Calibration Uncertainty 10 Output Range 0 to 2 5 V 0 to 5 V Measurement Range 0 to 100 W m 2 Measurement Repeatability Less than 0 5 Long term Drift Less than 2 per year Non linearity Less than 1 Response Time Less than 1 ms Field of View 180 Spectral Range 300 to 400 nm wavelengt...

Page 7: ...error for Apogee SU 200 series UV A sensors is approximately 2 and 5 at solar zenith angles of 45 and 75 respectively Mean cosine response of four Apogee UV A sensors Cosine response was calculated as the relative difference of UV A sensors from the mean of replicate reference UV A sensors deployed outdoors These data are the average of the AM and PM response ...

Page 8: ...Spectral Response Spectral response estimate of Apogee SU 200 UV A sensors Spectral response was modeled from sensitivity of the photodetector and transmittance of the diffuser ...

Page 9: ... minimize azimuth error the sensor should be mounted with the cable pointing toward true north in the northern hemisphere or true south in the southern hemisphere Azimuth error is typically less than 1 but it is easy to minimize by proper cable orientation In addition to orienting the cable to point toward the nearest pole the sensor should also be mounted such that obstructions e g weather statio...

Page 10: ...ee directly to ensure ordering the proper pigtail configuration Alignment When reconnecting a sensor arrows on the connector jacket and an aligning notch ensure proper orientation Disconnection for extended periods When disconnecting the sensor for an extended period of time from a station protect the remaining half of the connector still on the station from water and dirt with electrical tape or ...

Page 11: ...n In order to maximize measurement resolution and signal to noise ratio the input range of the measurement device should closely match the output range of the UV sensor The amplification circuit requires a power supply of 3 3 to 24 V DC SU 202 or 5 5 to 24 V DC SU 205 NOTE to prevent sensor damage DO NOT connect the sensor to a power source greater than 24 V DC Wiring for SU 202 and SU 205 Black N...

Page 12: ...r full sunlight Calibration Factor 0 04 W m 2 per mV Sensor Output Signal mV UV A W m 2 0 04 1500 60 Example of UV A measurement with an Apogee SU 202 sensor Full sunlight yields UV A radiation on a horizontal plane at the Earth s surface of approximately 60 W m 2 This yields an output signal of 1500 mV The signal is converted to UV A radiation by multiplying by the calibration factor of 0 04 W m ...

Page 13: ...te the SU 200 provides reasonable estimates of UV A radiation coming from electric lamps table provides spectral error estimates for UV A radiation measurements from radiation sources other than clear sky solar radiation For most common lamps the error is less than 10 The SU 200 is particularly useful for determining the UV A filtering capacity of the transparent plastic and glass barriers that ar...

Page 14: ...ay be necessary Dust or organic deposits are best removed using water or window cleaner and a soft cloth or cotton swab Salt deposits should be dissolved with vinegar and removed with a cloth or cotton swab Never use solvents such as alcohol or acetone to clean the sensor Use only gentle pressure when cleaning the diffuser with a cotton swab or soft cloth to avoid scratching the outer surface The ...

Page 15: ... of at least 25 mV or 50 mV to provide a measurement resolution of 1 W m 2 respectively An example datalogger program for Campbell Scientific dataloggers can be found on the Apogee webpage at http www apogeeinstruments com content UV Sensor CR1 Zero Offset Error With the use of certain dataloggers it is possible to measure a non zero voltage zero offset when the sensor output should be zero no UV ...

Page 16: ...an example of how to convert energy flux units to photon flux 1 Calculate the sensor output in units of J m 2 s 1 6 𝑚𝑉 10 𝑊𝑚 2 𝑚𝑉 60 𝑊 𝑚2 60 𝐽 𝑚2𝑠 2 Multiply the energy flux units by the conversion factor It s important to note that each light source needs a specific conversion factor The conversion factor used in the example equation is the sunlight conversion factor s 60 𝐽 𝑚2𝑠 0 327 𝜇𝑚𝑜𝑙 𝐽 19 62...

Page 17: ...d warranty items to our factory The warranty does not cover equipment that has been damaged due to the following conditions 1 Improper installation or abuse 2 Operation of the instrument outside of its specified operating range 3 Natural occurrences such as lightning fire etc 4 Unauthorized modification 5 Improper or unauthorized repair Please note that nominal accuracy drift is normal over time R...

Page 18: ...geeinstruments com to discuss repair or replacement options OTHER TERMS The available remedy of defects under this warranty is for the repair or replacement of the original product and Apogee Instruments is not responsible for any direct indirect incidental or consequential damages including but not limited to loss of income loss of revenue loss of profit loss of wages loss of time loss of sales a...

Reviews: