apogee INSTRUMENTS MQ-610 ePAR Meter Owner’s Manual

apogee INSTRUMENTS MQ-610 ePAR Meter

Product Information

The ePAR Meter, model MQ-610, is a self-contained handheld meter and sensor designed and manufactured by Apogee Instruments, Inc. It is used to measure photosynthetic photon flux density (PPFD) in the 400-700 nm range, as well as far-red photons that contribute to canopy photosynthesis. The meter is equipped with a sensor that measures the minimum quantity of radiation, known as a quantum, involved in physical interactions such as absorption by photosynthetic pigments. This sensor can be considered an “extended range” quantum sensor, as it measures a wider range of wavelengths. The ePAR Meter is compliant with relevant Union harmonization legislation, including the Electromagnetic Compatibility (EMC)  Directive (2014/30/EU), Restriction of Hazardous Substances (RoHS2) Directive (2011/65/EU), and Amending Annex II to Directive 2011/65/EU (RoHS 3). It meets the standards for the restriction of hazardous substances.

The meter has the following specifications:

• Calibration Uncertainty: Less than 0.5%
• Measurement Range: Not specified
• Measurement Repeatability: Not specified
• Long-term Drift (Non-stability): Less than 2% per year
• Non-linearity: Not specified
• Response Time: Not specified
• Field of View: Not specified
• Spectral Range: 400-700 nm and far-red photons
• Directional (Cosine) Response: Not specified
• Azimuth Error: Not specified
• Tilt Error: Not specified
• Temperature Response: Not specified
• Uncertainty in Daily Total: Not specified
• Housing IP Rating: IP68
• Operating Environment: -40 to 70°C, 0 to 100% relative humidity; can be submerged in water up to depths of 30 m
• Meter Dimensions: Not specified
• Sensor Dimensions: Not specified
• Mass: Not specified
• Cable: Not specified
• Warranty: Not specified

Product Usage Instructions

1. Make sure the ePAR Meter is fully charged or has fresh batteries.
2. Turn on the meter by pressing the power button.
3. To measure PPFD in the 400-700 nm range, hold the sensor at the desired location above the canopy or plant surface.
4. The meter will display the PPFD value on the screen. Take note of the reading.
5. To measure far-red photons, ensure that the meter is in a location where it can capture both far-red and 400-700 nm photons.
6. Hold the sensor at the desired location and observe the displayed value, which represents the combined PPFD of far-red and 400-700 nm photons.
7. Record or analyze the data as needed for your application.
8. After usage, turn off the meter to conserve battery power.

INSTRUCTION

Radiation that drives photosynthesis is called photosynthetically active radiation (PAR) and, historically, is defined as total radiation across a range of 400 to 700 nm. PAR is almost universally quantified as photosynthetic photon flux density (PPFD) in units of micromoles per square meter per second (μmol m-2 s-1, equal to microEinsteins per square meter per second) summed from 400 to 700 nm (total number of photons from 400 to 700 nm). However, ultraviolet and far-red photons outside the defined PAR range of 400-700 nm can also contribute to photosynthesis and influence plant responses (e.g., flowering). Data from recent studies indicate that far-red photons synergistically interact with photons in the historically defined PAR range of 400-700 nm to increase photochemical efficiency in leaves (Hogewoning et al., 2012; Murakami et al., 2018; Zhen and van Iersel, 2017; Zhen et al., 2019). Measurements from whole plants and plant canopies indicate adding far-red photons (using far-red LEDs with peaks near 735 nm and outputting photons across a range of about 700-750 nm) to radiation sources outputting photons in the 400-700 nm range increases canopy photosynthesis equal to the addition of the same number of photons in the 400-700 nm range for multiple species, and C3 and C4 photosynthetic pathways, but far-red photons alone are photosynthetically inefficient and result in minimal photosynthesis (Zhen and Bugbee, 2020a; Zhen and Bugbee, 2020b). This research suggests that far-red photons drive canopy photosynthesis with similar efficiency as photons in the traditional PAR range when they are acting synergistically with photons in the 400-700 nm range, meaning when far-red photons are added to radiation sources outputting 400-700 nm photons. Thus, far-red photons need to be included in the definition of PAR (Zhen et al., 2021). Sensors that measure PPFD are often called quantum sensors due to the quantized nature of radiation. A quantum refers to the minimum quantity of radiation, one photon, involved in physical interactions (e.g., absorption by photosynthetic pigments). In other words, one photon is a single quantum of radiation. Sensors that function like traditional quantum sensors, but measure a wider range of wavelengths, can be thought of as an ‘extended range’ quantum sensor. Typical applications of traditional quantum sensors include incoming PPFD measurement over plant canopies in outdoor environments or in greenhouses and growth chambers and reflected or under-canopy (transmitted) PPFD measurement in the same environments. The extended photosynthetically active radiation (ePAR) sensor detailed in this manual uses a detector that is sensitive to radiation from 383-757 nm ± 5 nm, which allows it to measure photons from Far-red. Apogee Instruments MQ-610 meters consist of a handheld meter and a dedicated sensor that is connected by cable to an anodized aluminum housing. SQ-600 series ePAR sensors consist of a cast acrylic diffuser (filter), photodiode, and signal processing circuitry mounted in an anodized aluminum housing, and are potted solid with no internal air space. MQ series ePAR meters provide a real-time PFD reading on the LCD display, that determines the radiation incident on a planar surface (does not have to be horizontal), where the radiation emanates from all angles of a hemisphere. MQ series ePAR meters include manual and automatic data logging features for making spot-check measurements.

• Murakami et al. 2018. A Mathematical Model of Photosynthetic Electron Transport in Response to the Light Spectrum Based on Excitation Energy Distributed to Photosystems. Plant Cell Physiology. 59(8): 1643–1651.
• Zhen and Van Iersel. 2017. Far-red light is needed for efficient photochemistry and photosynthesis. Journal of Plant Physiology. 209: 115–122.
• Zhen et al. 2019. Far-red light enhances photochemical efficiency in a wavelength-dependent manner. Physiologia Plantarum. 167(1):21-33.
• Zhen and Bugbee. 2020a. Far-red photons have equivalent efficiency to traditional photosynthetic photons: Implications for redefining photosynthetically active radiation. Plant Cell and Environment. 2020; 1–14.
• Zhen and Bugbee. 2020b. Substituting Far-Red for Traditionally Defined Photosynthetic Photons Results in Equal Canopy Quantum Yield for CO2 Fixation and Increased Photon Capture During Long-Term Studies: Implications for Re-Defining PAR.
• Frontiers in Plant Science. 11:1-14. Zhen et al. 2021. Why Far-Red Photons Should Be Included in the Definition of Photosynthetic Photons and the Measurement of Horticultural Fixture Efficacy. Frontiers in Plant Science. 12:1-4.

SENSOR MODELS

Apogee MQ series PAR meters covered in this manual are self-contained and come complete with a handheld meter and sensor.

A sensor’s model number and serial number are located on a label on the backside of the handheld meter.

SPECIFICATIONS

| MQ-610
---|---
Calibration Uncertainty| ± 5 % (see Calibration Traceability below)
Measurement Range| 0 to 4000 µmol m-2 s-1
Measurement

Repeatability

| Less than 0.5 %
Long-term Drift

(Non-stability)

| Less than 2 % per year
Non-linearity| Less than 1 % (up to 4000 µmol m-2 s-1)
Response Time| Less than 1 ms
Field of View| 180°
Spectral Range| 383 to 757 nm ± 5 nm (wavelengths where the response is greater than 50 %; see Spectral

Response below)

Directional (Cosine)

Response

| ± 2 % at 45° zenith angle, ± 5 % at 75° zenith angle (see Directional Response below)
Azimuth Error| Less than 0.5 %
Tilt Error| Less than 0.5 %
Temperature Response| -0.11 ± 0.04 % per C
Uncertainty in Daily Total| Less than 5 %
Housing| Anodized aluminum body with acrylic diffuser
IP Rating| IP68
Operating Environment| -40 to 70 C; 0 to 100 % relative humidity; can be submerged in water up to depths of 30 m
Meter Dimensions| 126 mm length, 70 mm width, 24 mm height
Sensor Dimensions| 30.5 mm diameter, 37 mm height
Mass| 140 g (with 5 m of lead wire)
Cable| 2 m of two conductor, shielded, twisted-pair wire; additional cable available; TPR jacket
Warranty| 4 years against defects in materials and workmanship

Calibration Traceability
Apogee MQ series ePAR meters are calibrated through side-by-side comparison to the mean of four transfer standard sensors under a reference lamp. The reference sensors are recalibrated with a 200 W quartz halogen lamp traceable to the National Institute of Standards and Technology (NIST).

Spectral Response

Mean spectral response measurements of four replicate Apogee MQ-600 series ePAR Sensors. Incremental spectral response measurements were made at 10 nm increments across a wavelength range of 370 to 800 nm in a monochromator with an attached electric light source. Measured spectral data from each quantum sensor were refined and normalized by comparing the measured spectral response of the monochromator/electric light combination to measured spectral differences from a quantum sensor reference.

Cosine Response Directional, or cosine, response is defined as the measurement error at a specific angle of radiation incidence. Error for Apogee MQ-600 series ePAR Sensor is approximately ± 2 % and ± 5 % at solar zenith angles of 45° and 75°, respectively. Mean directional (cosine) response of seven Apogee series quantum sensors. Directional response measurements were made on the rooftop of the Apogee building in Logan, Utah. The directional response was calculated as the relative difference of quantum sensors from the mean of replicate reference quantum sensors (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

DEPLOYMENT AND INSTALLATION

Apogee MQ series ePAR meters are designed for spot-check measurements, and calculation of daily light integral (DLI; total number of photons incident on a planar surface over the course of a day) through the built-in logging feature. To accurately measure PFD incidents on a horizontal surface, the sensor must be level. For this purpose, each MQ model comes with a different option for mounting the sensor to a horizontal plane.

The AL-100 leveling plate is recommended for use with the MQ-610 (AL-100 leveling plate pictured). To facilitate mounting to a cross arm, the AL-120 mounting bracket is recommended.
The AM-310 Sensor Wand accessory incorporates a mounting fixture at the end of an extendable telescopic wand (up to 33 inches/84 cm). The wand is not suited for wet environments; however, it is excellent for greenhouses and growth chambers. Its ability to retract to a smaller size also makes it ideal for travel use

The AM-320 Saltwater Submersible Sensor Wand accessory incorporates a mounting fixture at the end of a 40-inch segmented fiberglass wand and is well-suited for saltwater use. The wand allows the user to place the sensor in hard-to- reach areas such as aquariums.

NOTE: The handheld meter portion of the instrument is not waterproof. Do not get the meter wet or leave the meter in high humidity environments for prolonged periods of time. Doing so can lead to corrosion that could void the warranty.

BATTERY INSTALLATION AND REPLACEMENT

Use a Phillips-head screwdriver to remove the screw from the battery cover. Remove the battery cover by slightly lifting and sliding the outer edge of the cover away from the meter.  To power the meter, slide the included battery (CR2320) into the battery holder, after removing the battery doorfrom the meter’s back panel.

The positive side (designated by a “+” sign) should be facing out from the meter circuit board.
NOTE : The battery cradle can be damaged by using an incorrectly sized battery. If the battery cradle is damaged, the circuit board will need to be replaced and the warranty will be void. To avoid this costly problem, use only a CR2320 battery.
Battery Removal
Press down on the battery with a screwdriver or similar object. Slide battery out.

If the battery is difficult to move, turn the meter on its side so that the opening for the battery is facing downward and tap the meter downward against an open palm to dislodge the battery enough so that it can be removed with your thumb to slide the battery out of the battery holder.

OPERATION AND MEASUREMENT

MQ series ePAR meters are designed with a user-friendly interface allowing quick and easy measurements.

• Press the power button to activate the LCD display. After two minutes of non-activity the meter will revert to sleep mode and the display will shut off to conserve battery life.
• Press the mode button to access the main menu, where manual or automatic logging is selected, and where the meter can be reset.
• Press the sample button to log a reading while taking manual measurements.
• Press the up button to make selections in the main menu. This button is also used to view and scroll through the logged measurements on the LCD display.
• Press the down button to make selections in the main menu. This button is also used to view and scroll through the logged measurements on the LCD display.

The LCD display consists of the total number of logged measurements in the upper right-hand corner, the real-time PFD value in the center, and the selected menu options along the bottom.

Logging: To choose between manual or automatic logging, push the mode button once and use the up/down buttons to make the appropriate selection (SMPL or LOG). Once the desired mode is blinking, press the mode button two more times to exit the menu. When in SMPL mode press the sample button to record up to 99 manual measurements (a counter in the upper right-hand corner of the LCD display indicates the total number of saved measurements). When in LOG mode the meter will power on/off to make a measurement every 30 seconds. Every 30 minutes the meter will average the sixty 30 second measurements and record the averaged value to memory. The meter can store up to 99 averages and will start to overwrite the oldest measurement once there are 99 measurements. Every 48 averaged measurements (making a 24-hour period), the meter will also store an integrated daily total in moles per meter squared per day (mol m-2 d-1).
Reset: To reset the meter, in either SMPL or LOG mode, push the mode button three times (RUN should be blinking), then while pressing the down button, press the mode button once. This will erase all the saved measurements in memory, but only for the selected mode. That is, performing a reset when in SMPL mode will only erase the manual measurements and performing a reset when in LOG mode will only erase the automatic measurements.
Review/Download Data: Each of the logged measurements in either SMPL or LOG mode can be reviewed on the LCD display by pressing the up/down buttons. To exit and return to the real-time readings, press the sample button. Note that the integrated daily total values are not accessible through the LCD and can only be viewed by downloading to a computer. Downloading the stored measurements will require the AC-100 communication cable and software (sold separately). The meter outputs data using the UART protocol and requires the AC-100 to convert from UART to USB, so standard USB cables will not work. Set up instructions and software can be downloaded from the Apogee website (http://www.apogeeinstruments.com/ac-100-communcation-cable/). Immersion Effect Correction Factor
When a radiation sensor is submerged in water, more of the incident radiation is backscattered out of the diffuser than when the sensor is in air (Smith, 1969; Tyler and Smith, 1970). This phenomenon is caused by the difference in the refractive index for air (1.00) and water (1.33) and is called the immersion effect. Without correction for the immersion effect, radiation sensors calibrated in air can only provide relative values underwater (Smith, 1969; Tyler and Smith, 1970). Immersion effect correction factors can be derived by making measurements in air and at multiple water depths at a constant distance from a lamp in a controlled laboratory setting. Apogee SQ-610 series ePAR sensors have an immersion effect correction factor of 1.25. This correction factor should be multiplied by PPFD measurements made underwater to yield accurate PPFD.
NOTE: The handheld meter portion of the instrument is not waterproof. Do not get the meter wet or leave the meter in high humidity environments for prolonged periods of time. Doing so can lead to corrosion that could void the warranty. Further information on underwater measurements and the immersion effect can be found on the Apogee webpage (http://www.apogeeinstruments.com /underwater-par-measurements/). Smith, R.C., 1969. An underwater spectral irradiance collector. Journal of Marine Research 27:341-351. Tyler, J.E., and R.C. Smith, 1970. Measurements of Spectral Irradiance Underwater. Gordon and Breach, New York, New York. 103 pages

APOGEE AMS SOFTWARE

Downloading data to a computer requires the AC-100 communication cable and the free ApogeeAMS software. The meter outputs data using the UART protocol and requires the AC-100 to convert from UART to USB, so standard USB cables will not work. The most recent version of ApogeeAMS software can be downloaded at http://www.apogeeinstruments.com/downloads/.

When the ApogeeAMS software is first opened, it will show a blank screen until communication with the meter is established. If you click “Open Port” it will say “connection failed.”

To establish communication, make sure the meter is plugged into your computer using the AC-100 communication cable. To connect click the dropdown menu button and “COM#” options will appear. For more details on how to figure out which COM is the right one, watch our video.

When you have connected to the correct COM#, the software will say “Connected”. Click “Sample Data” to view saved sample readings.

“Daily Totals” shows all the saved Daily Light Integral (DLI) totals per day.

Click “30 Min Avg” to see the meter’s 99, 30-minute averages.

To analyze the data, click on “File” and “Save As” to save the data as a .csv file. Or you can highlight the numbers, copy, and paste them into a blank Excel spreadsheet. Data will need to be comma delimited.

MAINTENANCE AND RECALIBRATION

Moisture or debris on the diffuser is a common cause of low readings. The sensor has a domed diffuser and housing for improved self-cleaning from rainfall, but materials can accumulate on the diffuser (e.g., dust during periods of low rainfall, salt deposits from evaporation of sea spray or sprinkler irrigation water) and partially block the optical path. 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 soft cloth or cotton swab. Never use an abrasive material or cleaner on the diffuser. Although Apogee sensors are very stable, nominal accuracy drift is normal for all research -grade sensors. To ensure maximum accuracy, we generally recommend sensors are sent in for recalibration every two years,although you can often wait longer according to your particular tolerances.

TROUBLESHOOTING AND CUSTOMER SUPPORT

Verify Functionality
Pressing the power button should activate the LCD and provide a real-time PFD reading. Direct the sensor head toward a light source and verify the PFD readine resoonds. Increase and decrease the distance from the sensor to the lieht source to verify that the readine chanees proportionally (decreasine PFD with increasine distance and increasing PFD with decreasing distance). Blocking all radiation from the sensor should force the PFD reading to
Battery Life
When the meter is maintained properly the coin cell battery (CR2320) should last for many months, even after continuous use. The low battery indicator will appear in the upper left-hand corner of the LCD display when the battery voltage drops below 2.8 V DC. The meter will still function correctly for some time, but once the battery is drained the pushbuttons will no longer respond and any logged measurements will be lost. Pressing the power button to turn off the meter will actually put it in sleep mode, where there is still a slight amount of current draw. This is necessary to maintain the logged measurements in memory. Therefore, it is recommended to remove the battery when storing the meter for many months at a time, in order to preserve battery life.
Low-Battery Error after Battery Replacement
A master reset will usually correct this error. please see the master reset section for details and cautions. if a master reset does not remove the low battery indicator, please double check that the voltage of your new battery is above 2.8 V, this is the threshold for the indicator to turn on.
Master Reset
it a meter ever becomes non-responsive or experiences anomalies, such as a low battery indicator even after replacing the old battery, a master reset can be performed that may correct the problem. Note that a master reset will erase all logged measurements from memory.

• Step 1: press the power button so that the LCD display is activated.
• Step 2: Slide the battery out of the holder, which will cause the LCD display to fade out.
• Step 3: After a few seconds, slide the battery back into the holder.

The LCD display will flash all segments and then show a revision number (e.g., “R1.0*). This indicates the master reset was performed and the display should return to normal.

Error Codes and Fixes
Error codes will appear in place of the real-time reading on the LCD display and will continue to flash until the problem is corrected. Contact Apogee if the following fixes do not rectify the problem.

• Err 1: battery voltage out of range. Fix: replace CR2320 battery and perform master reset.
• Err 2: sensor voltage out of range. Fix: perform master reset.
• Err 3: not calibrated. Fix: perform master reset.
• Err 4: CPU voltage below minimum. Fix: replace CR2320 battery and perform master reset.

Modifying Cable Length
Although it is possible to splice additional cable to the separate sensor of the appropriate MQ model, note that the cable wires are soldered directly into the circuit board of the meter. Care should be taken to remove the back panel of the meter in order to access the board and splice on the additional cable, otherwise two splices would need to be made between the meter and sensor head. See Apogee webpage for further 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
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 another 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.

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 the service item. Call 435-245-8012 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 [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

CONTACT

• APOGEE INSTRUMENTS, INC.
• 721 WEST 1800 NORTH, LOGAN, UTAH 84321, USA
• TEL: 435-792-4700
• FAX: 435-787-8268
• WEB: APOGEEINSTRUMENTS.COM.

Copyright © 2022 Apogee Instruments, Inc.

References

• AC-100: Communication Cable - Apogee Instruments, Inc.
• Software Downloads - Datalogger Programs | Apogee Instruments
• How to Make a Weatherproof Cable Splice
• Recalibration and Repair | Apogee Instruments
• Underwater PAR Measurements | Apogee Instruments

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