Apogee Instruments S2-441 User manual

APOGEE INSTRUMENTS, INC. | 721 WEST 1800 NORTH, LOGAN, UTAH 84321, USA
TEL: [phone] | FAX: [phone] | WEB: APOGEEINSTRUMENTS.COM
Copyright © 2022 Apogee Instruments, Inc.
OWNER’S MANUAL
PAR-FAR SENSOR
Models S2-441
Rev: 31-Mar-2022

TABLE OF CONTENTS
Owner’s Manual ............................................................................................................................................................................... 1
Certificate of Compliance......................................................................................................................................................... 3
Introduction ............................................................................................................................................................................. 4
Sensor Models ......................................................................................................................................................................... 5
Specifications ........................................................................................................................................................................... 6
Deployment and Installation.................................................................................................................................................... 9
Cable Connectors................................................................................................................................................................... 10
Operation and Measurement ................................................................................................................................................ 11
Maintenance and Recalibration............................................................................................................................................. 15
Troubleshooting and Customer Support................................................................................................................................ 16
Return and Warranty Policy................................................................................................................................................... 17

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: S2-441
Type: PAR-FAR 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 50581:2012 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, March 2022
Bruce Bugbee
President
Apogee Instruments, Inc.

INTRODUCTION
Specific wavelengths of radiation trigger distinct plant responses. Radiation that drives photosynthesis is called
photosynthetically active radiation (PAR) and is typically defined as total radiation across a wavelength range of
400 to 700 nm. PAR is almost universally quantified as photosynthetic photon flux density (PPFD), the sum of
photons from 400 to 700 nm in units of micromoles per square meter per second (µmol m-2 s-1, equal to
microEinsteins m-2 s-1). While microEinsteins and micromoles are equal (one Einstein = one mole of photons), the
Einstein is not an SI unit, so expressing PPFD as µmol m-2 s-1 is preferred. Daily total PPFD is typically reported in
units of moles of photons per square meter per day (mol m-2 d-1) and is often called daily light integral (DLI).
The acronym PPF is also used and refers to the photosynthetic photon flux. The acronyms PPF and PPFD refer to
the same variable. Both terms are used because there is not a universal definition of the term flux. Flux is
sometimes defined as per unit area per unit time and sometimes defined as per unit time only. PPFD is used in this
manual.
In addition to wavelengths within the PAR range, far-red wavelengths (those just beyond 700 nm) are of particular
interest because they influence plant photosynthetic and morphogenic activity. Phytochrome pigments sensitive
to varying ratios of red and far-red light provide information to the plant about the light environment, and
therefore, influence growth patterns. Increasing the fraction of PAR, and specifically red radiation, relative to far-
red radiation indicates less shading and generally results in more conservative vertical growth patterns. Increasing
far-red radiation relative to PAR indicates more shading and results in more aggressive vertical growth patterns.
Sensors that measure PPFD are often called quantum sensors because they measure the number of incident
photosynthetic photons and one photon is a single quantum of radiation. Far-red sensors are similar in that they
measure incident photons, but the wavelength range is different. Far-red sensors can be thought of as quantum
sensors that measure radiation just beyond 700 nm. Sensors that pair detectors to measure both PPFD and far-red
photon flux density can be called PAR-FAR sensors.
The primary application of PAR-FAR sensors is monitoring plant light environments, including calculation of the far-
red fraction (far-red photon flux density / sum of PPFD and far-red photon flux density), in photobiology studies
(e.g., researching plant morphogenic activity).
Apogee Instruments S2 series PAR-FAR sensors consist of a cast acrylic diffuser, pair of photodetectors that
measure PAR and far-red wavelength ranges (400-700 nm for PAR, 700-760 nm for far-red), and signal processing
circuitry mounted in an anodized aluminum housing. A cable to connect the radiometer measurement device is
also included. Sensors are designed for continuous measurement in indoor and outdoor environments. S2-100
series sensors output two voltage signals, one from each photodetector, that are directly proportional to the
radiation incident on a planar surface (does not have to be horizontal), where the radiation emanates from all
angles of a hemisphere.

SENSOR MODELS
This manual covers the SDI-12 model S2-441 (in bold below). Additional models are covered in their respective
manuals.
Model
Signal
S2-141
Voltage
S2-441
SDI-12
S2-442
Modbus
A sensor’s model number and serial number are
located on the bottom of the sensor. If you need
the manufacturing date of your sensor, please
contact Apogee Instruments with the serial
number of your sensor.

SPECIFICATIONS
Calibration Traceability
The PAR sensor in Apogee S2 series PAR-FAR sensors are calibrated through side-by-side comparison to the mean
of four transfer standard quantum sensors under a reference lamp. The transfer standard quantum sensors are
calibrated with a quartz halogen lamp traceable to the National Institute of Standards and Technology (NIST).
The far-red sensor in Apogee S2 series PAR-FAR sensors are calibrated through side-by-side comparison to the
mean photon flux density of four transfer standard far-red radiometers under far-red LEDs (735 nm peak, 710-760
nm range). The transfer standard far-red sensors are calibrated against a spectroradiometer (Apogee Instruments
model PS-300) under the same far-red LEDs. The spectroradiometer is calibrated with a quartz halogen lamp
traceable to the National Institute of Standards and Technology (NIST).
S2-441
Power Supply
5.5 to 24 V DC
Current Draw
1.4 mA (quiescent), 1.8 mA (active)
Calibration Factor (reciprocal
of sensitivity)
Custom for each sensor and stored in firmware
Calibration Uncertainty
± 5 %
Output Range
SDI-12
Measurement Repeatability
Less than 1 %
Long-term Drift
Less than 2 % per year
Non-linearity
Less than 1 % (up to 4000 µmol m⁻² s⁻¹) (PAR)
Less than 1 % (up to 1000 µmol m⁻² s⁻¹) (Far-red)
Response Time
0.6 s, time for detector signal to reach 95 % following a step change; fastest data
transmission rate for SDI-12 circuitry is 1 s
Field of View
180°
Spectral Ranges
389 to 692 nm ± 5 nm (PAR)
702 to 761 nm ± 5 nm (Far-red)
Directional (Cosine) Response
± 2 % at 45°; ± 5 % at 75° zenith angle
Temperature Response
Less than 0.1 % per C
Housing
Anodized aluminum body with acrylic diffuser
IP Rating
IP68
Operating Environment
-40 to 70 C; 0 to 100 % relative humidity
Dimensions
30.5 mm diameter, 37 mm height
Mass (with 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

Cosine Response
Directional, or cosine, response is defined as the
measurement error at a specific angle of radiation
incidence. Error for Apogee S2 series PAR-FAR
sensors is approximately ± 2 % and ± 5 % at solar
zenith angles of 45° and 75°, respectively.
Mean directional (cosine) response
of seven apogee PAR-FAR sensors.
Directional response measurements
were made on the rooftop of the
Apogee building in Logan, Utah.
Directional response was calculated
as the relative difference of PAR-FAR
sensors from the mean of replicate
PAR detectors (LI-COR models LI-190
and LI-190R, Kipp & Zonen model
PQS 1). Data were also collected in
the laboratory using a reference
lamp and positioning the sensor at
varying angles.

Spectral Response
Spectral response of PAR detector
(blue) and Far-red detector (red)
compared to the defined response
of plants to radiation (dashed).

DEPLOYMENT AND INSTALLATION
Mount the sensor to a solid surface with the nylon mounting screw provided. To accurately measure PPFD incident
on a horizontal surface, the sensor must be level. An Apogee Instruments model AL-100 leveling plate is
recommended for this purpose. To facilitate mounting on a cross arm, an Apogee Instruments model AM-110
mounting bracket 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 0.5 %, 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 green cap should be removed from the sensor. The green cap can be used as a protective covering
for the sensor when it is not in use.
Nylon Screw: 10-32 x 3/8
Model: AL-110
Model: AL-120
Nylon Screw: 10-32 x 3/8

CABLE CONNECTORS
Apogee sensors offer cable connectors to simplify the
process of removing sensors from weather stations
for calibration (the entire cable does not have to be
removed from the station and shipped with the
sensor).
The ruggedized M8 connectors are rated IP68, made
of corrosion-resistant marine-grade stainless-steel,
and designed for extended use in harsh
environmental conditions.
Cable connectors are attached directly to the head.
Instructions
Pins and Wiring Colors: All Apogee
connectors have six pins, but not all pins are
used for every sensor. There may also be
unused wire colors inside the cable. To
simplify datalogger connection, we remove
the unused pigtail lead colors at the
datalogger end of the cable.
If a replacement cable is required, please
contact Apogee 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 other method.
A reference notch inside the connector ensures
proper alignment before tightening.
When sending sensors in for calibration, only send the sensor head.
Tightening: Connectors are designed to be
firmly finger-tightened only. There is an o-
ring inside the connector that can be overly
compressed if a wrench is used. Pay
attention to thread alignment to avoid
cross-threading. When fully tightened, 1-2
threads may still be visible.
WARNING: Do not tighten the connector by
twisting the black cable or sensor head, only
twist the metal connector (blue arrows).
Finger-tighten firmly

OPERATION AND MEASUREMENT
The S2-441 PAR-FAR sensor has a SDI-12 output, where PPFD and far-red photon flux density are returned in digital
format. Measurement of S2-441 PAR-FAR sensors requires a measurement device with SDI-12 functionality that
includes the M or C command.
Wiring
Sensor Calibration
All Apogee SDI-12 S2 sensor models have sensor-specific calibration coefficients determined during the custom
calibration process. Coefficients are programmed into sensor microcontrollers at the factory.
SDI-12 Interface
The following is a brief explanation of the serial digital interface SDI-12 protocol instructions used in Apogee S2-
400 series PAR-FAR sensors. For questions on the implementation of this protocol, please refer to the official
version of the SDI-12 protocol: http://www.sdi-12.org/specification.php (version 1.4, August 10, 2016).
Overview
During normal communication, the data recorder sends a packet of data to the sensor that consists of an address
and a command. Then, the sensor sends a response. In the following descriptions, SDI-12 commands and
responses are enclosed in quotes. The SDI-12 address and the command/response terminators are defined as
follows:
Sensors come from the factory with the address of “0” for use in single sensor systems. Addresses “1 to 9” and
“A to Z”, or “a to z”, can be used for additional sensors connected to the same SDI-12 bus.
“!” is the last character of a command instruction. In order to be compliant with SDI-12 protocol, all commands
must be terminated with a “!”. SDI-12 language supports a variety of commands. Supported commands for the
Apogee Instruments SQ-400 series two-band radiometers are listed in the following table (“a” is the sensor
address. The following ASCII Characters are valid addresses: “0-9” or “A-Z”). Please note that SDI-12 commands are
case-sensitive.
White: Positive (signal from sensor)
Red: Input Power
Black: Ground (from sensor signal and output power)
Clear: Shield/Ground

Supported Commands for Apogee Instruments S2-400 Series PAR-FAR Sensors
Instruction Name
Instruction Syntax
Description
Address Query Command
?!
Used when the address is unknown to have the sensor
identify its address, all sensors on data line respond
Change Address Command
aAb!
Changes the sensor address from a to b
Acknowledge Active Command
a!
Responds if the sensor with address a is on the line
Send Identification Command (“I”
command)
aI!
Responds with sensor information
Calibration Verification (“V” command)
aV!
Retrieves calibration coefficients
Measurement Command (“M”
command)
aM!
Tells the sensor to take a measurement
Measurement Command w/ Check
Character (“M” command)
aMC!
Tells the sensor to take a measurement and return it
with a check character
Concurrent Measurement Command
(“C” command)
aC!
Used to take a measurement when more than one
sensor is used on the same data line
Concurrent Measurement Command w/
Check Character (“C” command)
aCC!
Used to take a measurement when more than one
sensor is used on the same data line. Data is returned
with a check character.
Get Data Command (“D” command)
aD0!
Retrieves the data from a sensor
Running Average Command
aXAVG!
Returns or sets the running average for sensor
measurements.
Make Measurement Command: M!
The make measurement command signals a measurement sequence to be performed. Data values generated in
response to this command are stored in the sensor's buffer for subsequent collection using “D” commands. Data
will be retained in sensor storage until another “M”, “C”, or “V” command is executed. M commands are shown in
the following examples:
Command
Response
Response to 0D0!
aM! or aM0!
a0011<cr><If>
Returns Ratio (PAR / Far-red), Far-red Percentage ((FR / total) x 100) values
aM1!
a0012<cr><If>
Returns calibrated lower wavelength output and calibrated upper wavelength
output in µmol m⁻² s⁻¹
aM2!
a0012<cr><If>
Returns lower wavelength detector millivolts and upper wavelength detector
millivolts
aM3!
a0013<cr><If>
Returns angle offset from vertical in degrees. (0 degrees if pointed up, 180 degrees
if pointed down.)
aMC0!
a0011<cr><If>
Returns Ratio (PAR / Far-red), Far-red Percentage ((FR / total) x 100) values w/CRC
aMC1!
a0012<cr><If>
Returns calibrated lower wavelength output and calibrated upper wavelength
output in µmol m⁻² s⁻¹ w/ CRC
aMC2!
a0012<cr><If>
Returns lower wavelength detector millivolts and upper wavelength detector
millivolts w/ CRC
aMC3!
A0013<cr><If>
Returns angle offset from vertical in degrees. (0 degrees if pointed up, 180 degrees
if pointed down.) w/ CRC
“<cf>” is a carriage return and “<lf>” is line feed
where a is the sensor address (“0-9”, “A-Z”, “a-z”) and M is an upper-case ASCII character.

The data values are separated by the sign “+”, as in the following example (0 is the address):
Command
Sensor Response
Sensor Response when data is ready
0M0!
00011<cr><lf>
0<cr><lf>
0D0!
0+2.0+20.0<cr><lf>
0M1!
00012<cr><lf>
0<cr><lf>
0D0!
0+400.0+20.0<cr><lf>
0M2!
00012<cr><If>
0<cr><If>
0D0!
0+40.0+2.0<cr><If>
0M3!
00013<cr><If>
0<cr><If>
0D0!
0+35.2<cr><If>
Where M1! output is in µmol m-2 s-1.
Concurrent Measurement Command: aC!
A concurrent measurement is one which occurs while other SDI-12 sensors on the bus are also making
measurements. This command is similar to the “aM!” command, however, the nn field has an extra digit and the
sensor does not issue a service request when it has completed the measurement. Communicating with other
sensors will NOT abort a concurrent measurement. Data values generated in response to this command are stored
in the sensor's buffer for subsequent collection using “D” commands. The data will be retained in the sensor until
another “M”, “C”, or “V” command is executed:
Command
Response
Response to 0D0!
aC! or aC0!
a00101<cr><lf>
Returns Ratio (PAR / Far-red), Far-red Percentage ((FR / total) x 100) values
aC1!
a00102<cr><lf>
Returns calibrated lower wavelength output and calibrated upper wavelength
output in µmol m⁻² s⁻¹
aC2!
a00102<cr><lf>
Returns lower wavelength detector millivolts and upper wavelength detector
millivolts
aC3!
a00103<cr><lf>
Returns angle offset from vertical in degrees. (0 degrees if pointed up, 180
degrees if pointed down.)
aCC! or aCC0!
a00101<cr><lf>
Returns Ratio (PAR / Far-red), Far-red Percentage ((FR / total) x 100) values
w/CRC
aCC1!
a00102<cr><lf>
Returns calibrated lower wavelength output and calibrated upper wavelength
output in µmol m⁻² s⁻¹w/CRC
aCC2!
a00102<cr><lf>
Returns lower wavelength detector millivolts and upper wavelength detector
millivolts w/CRC
aCC3!
a00103<cr><lf>
Returns angle offset from vertical in degrees. (0 degrees if pointed up, 180
degrees if pointed down.) w/CRC
where a is the sensor address (“0-9”, “A-Z”, “a-z”, “*”, “?”) and C is an upper-case ASCII character.
For example (0 is the address):
Command
Sensor Response
0C0!
000101<cr><lf>
0D0!
0+2.0+20.0<cr><lf>
0C1!
000102<cr><If>
0D0!
0+400.0+20.0<cr><lf>
0C2!
000102<cr><lf>
0D0!
0+40.0+2.0<cr><If>
0C3!
000103<cr><If>
0D0!
0+35.2<cr><If>
Where C1! output is in µmol m-2 s-1.

Change Sensor Address: aAb!
The change sensor address command allows the sensor address to be changed. If multiple SDI-12 devices are on
the same bus, each device will require a unique SDI-12 address. For example, two SDI-12 sensors with the factory
address of 0 requires changing the address on one of the sensors to a non-zero value in order for both sensors to
communicate properly on the same channel:
Command
Response
Description
aAb!
b<cr><lf>
Change the address of the sensor
where a is the current (old) sensor address (“0-9”, “A-Z”), A is an upper-case ASCII character denoting the
instruction for changing the address, b is the new sensor address to be programmed (“0-9”, “A-Z”), and ! is the
standard character to execute the command. If the address change is successful, the datalogger will respond with
the new address and a <cr><lf>.
Send Identification Command: aI!
The send identification command responds with sensor vendor, model, and version data. Any measurement data
in the sensor's buffer is not disturbed:
Command
Response
Description
"aI!"
a13Apogee S2-441vvvxx…xx<cr><lf>
The sensor serial number and other identifying values are
returned
where a is the sensor address (“0-9”, “A-Z”, “a-z”, “*”, “?”), 441 is the sensor model number, vvv is a three
character field specifying the sensor version number, and xx...xx is serial number.
Running Average Command
The running average command can be used to set or query the number of measurements that are averaged
together before returning a value from a M! or MC! command. For example, if a user sends the command
“0XAVG10!” to sensor with address 0, that sensor will average 10 measurements before sending the averaged
value to the logger. To turn off averaging, the user should send the command “aXAVG1” to the sensor. To query
the sensor to see how many measurements are being averaged, send the command “aXAVG!” and the sensor will
return the number of measurements being averaged (see table below). The default for sensors is to have averaging
turned off.
Command Name
Characters Sent
Response
Description
Query running
Average
aXAVG!
an
a = sensor address, n = number of measurements used in
average calculation. Note: nmay be multiple digits.
Set running
Average
aXAVGn!
a
a = sensor address, n = number of measurements to be used in
average calculation. Note: nmay be any value from 1 to 100.

MAINTENANCE AND RECALIBRATION
Blocking of the optical path between the target and detector can cause low readings. Occasionally, accumulated
materials on the diffuser can block the optical path in three common ways:
1. Moisture or debris on the diffuser.
2. Dust during periods of low rainfall.
3. Salt deposit accumulation from evaporation of sea spray or sprinkler irrigation water.
Apogee Instruments PAR-FAR sensors have a domed diffuser and housing for improved self-cleaning from rainfall
but active cleaning may 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. Salt deposits cannot be removed with solvents such as alcohol or acetone. Use only gentle pressure when
cleaning the diffuser with a cotton swab or soft cloth, to avoid scratching the outer surface. The solvent should be
allowed to do the cleaning, not mechanical force. Never use an abrasive material or cleaner on the diffuser.
It is recommended that PAR-FAR sensors be recalibrated every two years. See the Apogee webpage for details
regarding return of sensors for recalibration (http://www.apogeeinstruments.com/tech-support-recalibration-
repairs/).

TROUBLESHOOTING AND CUSTOMER SUPPORT
Independent Verification of Functionality
If the sensor does not communicate with the datalogger, use an ammeter to check the current drain. It should be
near 1.4 mA when the sensor is not communicating and spike to approximately 1.8 mA when the sensor is
communicating. Any current drain greater than approximately 6 mA indicates a problem with power supply to the
sensors, wiring of the sensor, or sensor electronics.
Compatible Measurement Devices (Dataloggers/Controllers/Meters)
Any datalogger or meter with SDI-12 functionality that includes the M or C command.
An example datalogger program for Campbell Scientific dataloggers can be found on the Apogee webpage at
http://www.apogeeinstruments.com/downloads/#datalogger.
Modifying Cable Length
SDI-12 protocol limits cable length to 60 meters. For multiple sensors connected to the same data line, the
maximum is 600 meters of total cable (e.g., ten sensors with 60 meters of cable per sensor). See Apogee webpage
for details on how to extend sensor cable length (http://www.apogeeinstruments.com/how-to-make-a-
weatherproof-cable-splice/).

RETURN AND WARRANTY POLICY
RETURN POLICY
Apogee Instruments will accept returns within 30 days of purchase as long as the product is in new condition (to be
determined by Apogee). Returns are subject to a 10 % restocking fee.
WARRANTY POLICY
What is Covered
All products manufactured by Apogee Instruments are warranted to be free from defects in materials and craftsmanship
for a period of four (4) years from the date of shipment from our factory. To be considered for warranty coverage an
item must be evaluated by Apogee.
Products not manufactured by Apogee (spectroradiometers, chlorophyll content meters, EE08-SS probes) are covered
for a period of one (1) year.
What is Not Covered
The customer is responsible for all costs associated with the removal, reinstallation, and shipping of suspected warranty
items to our factory.
The warranty does not cover equipment that has been damaged due to the following conditions:
1. Improper installation, use, 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. Routine recalibration of sensors/meters is considered part of
proper maintenance and is not covered under warranty.
Who is Covered
This warranty covers the original purchaser of the product or other party who may own it during the warranty period.
What Apogee Will Do
At no charge Apogee will:
1. Either repair or replace (at our discretion) the item under warranty.
2. Ship the item back to the customer by the carrier of our choice.
Different or expedited shipping methods will be at the customer’s expense.

APOGEE INSTRUMENTS, INC. | 721 WEST 1800 NORTH, LOGAN, UTAH 84321, USA
TEL: [phone] | FAX: [phone] | WEB: APOGEEINSTRUMENTS.COM
Copyright © 2022 Apogee Instruments, Inc.
How To Return An Item
1. Please do not send any products back to Apogee Instruments until you have received a Return Merchandise
Authorization (RMA) number from our technical support department by submitting an online RMA form at
www.apogeeinstruments.com/tech-support-recalibration-repairs/. We will use your RMA number for tracking of the
service item. Call [phone] or email [email protected] with questions.
2. For warranty evaluations, send all RMA sensors and meters back in the following condition: Clean the sensor’s exterior
and cord. Do not modify the sensors or wires, including splicing, cutting wire leads, etc. If a connector has been attached
to the cable end, please include the mating connector –otherwise the sensor connector will be removed in order to
complete the repair/recalibration. Note: When sending back sensors for routine calibration that have Apogee’s standard
stainless-steel connectors, you only need to send the sensor with the 30 cm section of cable and one-half of the
connector. We have mating connectors at our factory that can be used for calibrating the sensor.
3. Please write the RMA number on the outside of the shipping container.
4. Return the item with freight pre-paid and fully insured to our factory address shown below. We are not responsible for
any costs associated with the transportation of products across international borders.
Apogee Instruments, Inc.
721 West 1800 North Logan, UT
84321, USA
5. Upon receipt, Apogee Instruments will determine the cause of failure. If the product is found to be defective in terms
of operation to the published specifications due to a failure of product materials or craftsmanship, Apogee Instruments
will repair or replace the items free of charge. If it is determined that your product is not covered under warranty, you
will be informed and given an estimated repair/replacement cost.
PRODUCTS BEYOND THE WARRANTY PERIOD
For issues with sensors beyond the warranty period, please contact Apogee at t[email protected] 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 data, loss of wages, loss of time, loss of sales, accruement of debts
or expenses, injury to personal property, or injury to any person or any other type of damage or loss.
This limited warranty and any disputes arising out of or in connection with this limited warranty ("Disputes") shall be
governed by the laws of the State of Utah, USA, excluding conflicts of law principles and excluding the Convention for the
International Sale of Goods. The courts located in the State of Utah, USA, shall have exclusive jurisdiction over any
Disputes.
This limited warranty gives you specific legal rights, and you may also have other rights, which vary from state to state
and jurisdiction to jurisdiction, and which shall not be affected by this limited warranty. This warranty extends only to
you and cannot by transferred or assigned. If any provision of this limited warranty is unlawful, void, or unenforceable,
that provision shall be deemed severable and shall not affect any remaining provisions. In case of any inconsistency
between the English and other versions of this limited warranty, the English version shall prevail.
This warranty cannot be changed, assumed, or amended by any other person or agreement