Apogee Instruments SU-300-SS User manual

APOGEE INSTRUMENTS, INC. | 721 WEST 1800 NORTH, LOGAN, UTAH 84321, USA
TEL: [phone] | FAX: [phone] | WEB: APOGEEINSTRUMENTS.COM
Copyright © 2023 Apogee Instruments, Inc.
OWNER’S MANUAL
ULTRAVIOLET INDEX &
ULTRAVIOLET-B SENSOR
Models SU-300-SS
Rev: 5-Jan-2023

TABLE OF CONTENTS
Owner’s Manual ............................................................................................................................................................................... 1
Certificates of Compliance ....................................................................................................................................................... 3
Introduction ............................................................................................................................................................................. 5
Sensor Models ......................................................................................................................................................................... 6
Specifications ........................................................................................................................................................................... 7
Deployment and Installation.................................................................................................................................................. 10
Cable Connectors................................................................................................................................................................... 11
Operation and Measurement ................................................................................................................................................ 12
Maintenance and Recalibration............................................................................................................................................. 16
Troubleshooting and Customer Support................................................................................................................................ 17
Return and Warranty Policy................................................................................................................................................... 18

CERTIFICATE OF COMPLIANCE
EU Declaration of Conformity
This declaration of conformity is issued under the sole responsibility of the manufacturer:
Apogee Instruments, Inc.
721 W 1800 N
Logan, Utah 84321
USA
for the following product(s):
Models: SU-300
Type: Ultraviolet Index and Ultraviolet-B Sensor
The object of the declaration described above is in conformity with the relevant Union harmonization legislation:
2014/30/EU Electromagnetic Compatibility (EMC) Directive
2011/65/EU Restriction of Hazardous Substances (RoHS 2) Directive
2015/863/EU Amending Annex II to Directive 2011/65/EU (RoHS 3)
Standards referenced during compliance assessment:
EN 61326-1:2013 Electrical equipment for measurement, control, and laboratory use –EMC requirements
EN 63000:2018 Technical documentation for the assessment 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), polybrominated
diphenyls (PBDE), bis (2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP), and
diisobutyl phthalate (DIBP). However, please note that articles containing greater than 0.1 % lead concentration
are RoHS 3 compliant using exemption 6c.
Further note that Apogee Instruments does not specifically run any analysis on our raw materials or end products
for the presence of these substances, but we rely on the information provided to us by our material suppliers.
Signed for and on behalf of:
Apogee Instruments, January 2023
Bruce Bugbee
President
Apogee Instruments, Inc.

CERTIFICATE OF COMPLIANCE
UK Declaration of Conformity
This declaration of conformity is issued under the sole responsibility of the manufacturer:
Apogee Instruments, Inc.
721 W 1800 N
Logan, Utah 84321
USA
for the following product(s):
Models: SU-300
Type: Ultraviolet Index and Ultraviolet-B Sensor
The object of the declaration described above is in conformity with the relevant UK Statutory Instruments and
their amendments:
2016 No. 1091 The Electromagnetic Compatibility Regulations 2016
2012 No. 3032 The Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic
Equipment Regulations 2012
Standards referenced during compliance assessment:
BS EN 61326-1:2013 Electrical equipment for measurement, control, and laboratory use –EMC requirements
BS EN 63000:2018 Technical documentation for the assessment 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), polybrominated
diphenyls (PBDE), bis (2-ethylhexyl) phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP), and
diisobutyl phthalate (DIBP). However, please note that articles containing greater than 0.1 % lead concentration
are RoHS 3 compliant using exemption 6c.
Further note that Apogee Instruments does not specifically run any analysis on our raw materials or end products
for the presence of these substances, but we rely on the information provided to us by our material suppliers.
Signed for and on behalf of:
Apogee Instruments, January 2023
Bruce Bugbee
President
Apogee Instruments, Inc.

INTRODUCTION
Ultraviolet (UV) radiation constitutes a portion of the electromagnetic spectrum from 100 to 400 nm and is further
subdivided into three wavelength ranges: UV-A (315 to 400 nm), UV-B (280 to 315 nm), and UV-C (100 to 280 nm).
Much of the UV-B and all the UV-C wavelengths from the sun are absorbed by Earth’s atmosphere. There are also
multiple artificial UV light sources available.
Most UV sensors designed for sunlight measurements are sensitive to UV radiation in the UV-A or UV-B ranges.
Apogee Instruments SU-300 series UV-I/UV-B sensors detect UV radiation from 270 to 315 nm and are calibrated
to output UV Index measurements. UV Index is a relative metric that scales linearly with the intensity of UV
radiation that causes sunburn in humans. Measured UV Index can be converted to energy flux density units of
watts per square meter (W m-2, equal to Joules per second per square meter) or photon flux density units of
micromoles per square meter per second (µmol m-2 s-1).
Typical applications of UV-I/UV-B sensors include incoming UV radiation measurement in outdoor environments,
aimed at informing people of potential for UV exposure and sunburn, or in laboratory use with artificial light
sources (e.g., germicidal lamps).
Apogee Instruments SU-300 series UV-I/UV-B sensors consist of a sintered quartz diffuser, photodiode, and signal
processing circuitry mounted in an anodized aluminum housing and a cable to connect the sensor to a
measurement device. SU-300 sensors are designed for continuous UV-I/UV-B radiation measurement in indoor or
outdoor environments. The SU-300 series outputs an analog voltage that is directly proportional to UV-I/UV-B
radiation incident on a planar surface (does not have to be horizontal) where the radiation emanates from all
angles of a hemisphere.

The model number and serial number are located on
the bottom of the sensor. If manufacturing date of a
sensor is required, please contact Apogee Instruments
with the serial number of the sensor.
SENSOR MODELS
This manual covers the unamplified model SU-300 UV-I/UV-B sensor (listed below in bold). Additional models are
covered in their respective manuals.
Model
Signal
SU-300
0-2 mV
SU-321
SDI-12

SPECIFICATIONS
Calibration Traceability
Apogee UV-I/UV-B series sensors are calibrated through side-by-side comparison to the mean of four transfer
standard UV-I/UV-B sensors under sunlight. The transfer standard UV-I/UV-B sensors are calibrated through side-
by-side comparison to an Apogee model PS-300 spectroradiometer under sunlight (clear sky conditions) in Logan,
Utah. The PS-300 is calibrated with a quartz halogen lamp traceable to the National Institute of Standards and
Technology (NIST).
SU-300-SS
Power Supply
Self-Powered
Output (sensitivity)
0.1 mV per UV Index unit
Calibration Factor (reciprocal of
sensitivity)
10 UV Index units per mV
Calibration Uncertainty
± 10 %
Output Range
0 to 2 mV
Measurement Range
0 to 20 UV Index
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
270 to 315 nm (wavelengths where response is greater than 50 % of maximum; see Spectral
Response graph below)
Directional (Cosine) Response
± 2 % at 45°, ± 5 % at 75°
Temperature Response
Less than 0.1 % per C
Operating Environment
-30 to 85 C; 0 to 100 % relative humidity
Dimension
30.5 mm diameter, 37 mm height
Mass (5 m of cable)
140 g
Cable
5 m of shielded, twisted-pair wire; TPR jacket (high water resistance, high UV stability,
flexibility in cold conditions); pigtail lead wires; stainless steel (316), M8 connector located
25 cm from sensor head

Cosine Response
Cosine Response Graph
-10
-8
-6
-4
-2
0
2
4
6
8
10
010 20 30 40 50 60 70 80 90
Difference [%]
Solar Zenith Angle [°]
Directional, or cosine, response is
defined as the measurement error at
a specific angle of radiation incidence.
Directional error for Apogee SU-300
series UV-I/UV-B sensors is
approximately ± 2 % and ± 5 % at solar
zenith angles of 45° and 75°,
respectively.
Mean cosine response of four
Apogee UV-I/UV-B sensors. Cosine
response was calculated as the
relative difference of UV-I/UV-B
sensors from a reference UV-I/UV-B
sensor deployed outdoors. These
data are the average of the AM and
PM response.

Spectral Response
0.0001
0.0010
0.0100
0.1000
1.0000
10.0000
240 260 280 300 320 340 360 380 400
Relative Response
Wavelength [nm]
Spectral response estimate
of Apogee SU-300 UV-I/UV-B
sensors. Spectral response
was modeled from sensitivity
of the photodetector and
transmittance of the
diffuser. Gray line is the
Erythemal Action Spectrum
and provides a relative
indication of skin damage
caused by UV radiation.

DEPLOYMENT AND INSTALLATION
Mount the sensor to a solid surface with the nylon mounting screw provided. To accurately measure UV-I/UV-B
incident on a horizontal surface, the sensor must be level. An Apogee Instruments model AL-100 Leveling Plate is
recommended to level the sensor when used on a flat surface or being mounted to surfaces such as wood. To
facilitate mounting on a mast or pipe, the Apogee Instruments model AL-120 Solar Mounting Bracket with Leveling
Plate is recommended.
To 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 station tripod/tower or other instrumentation) do not shade the sensor. Once
mounted, the black cap should be removed from the sensor. The black cap can be used as a protective covering
for the sensor when it is not in use.
Nylon Screw: 10-32x3/8
Model AL-100
Nylon Screw: 10-32x3/8
Model AL-120