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Apogee Instruments DLI-500 PAR, Daily Light Integral, and Photoperiod Meter - Full-Spectrum 400-700 nm Light Measurement Tool for Plants & Agriculture

  • Based on 14 reviews
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Availability: Only 3 left in stock, order soon!
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Arrives Friday, Sep 27
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Style: DLI-500


Features

  • DLI-500 FULL-SPECTRUM METER: Gives research-grade measurements of PAR (PPFD), DLI and photoperiod from 400-700 nm under all grow-lighting used for plants. The meter takes spot measurements and records and displays daily light integral in molm-2d-1 and photoperiod in 0.2 hours increments for up to 99 days.
  • PAR/DLI/PHOTOPERIOD: Measuring and controlling the daily light integral (the total photosynthetic photons falling on a plant in a 24-hour period) and the hours of light a plant receives (photoperiod) is critical for optimizing plant health, triggering flowering, and inducing other plant morphology effects. PPFD, DLI, and photoperiod data can be viewed onscreen or downloaded via USB-C for analysis.
  • RUGGED AND READY TO USE: Built tough and rated IP65 to withstand harsh and wet environments. Unit can be placed directly on any level surface or mounted by attaching to commonly available camera tripods, clamps, or stakes using the standard camera-sized 14-20 threaded port on the bottom. Protective case, meter, soil stake, AAA batteries, USB-C cable, screwdriver, and QuickStart guide are included.
  • BUILT FOR SCIENTISTS AND SERIOUS GROWERS: Developed for use by the Apogee Instruments engineering team under the direction of world-renowned crop physiologist, Bruce Bugbee, PhD. Calibration is NIST traceable to accurately measure combined intensity of photons between 400 and 700 nm to give a single sunlight PAR reading within 5 % uncertainty. Unlike hobby-grade PAR meters that drift out of calibration quickly, our meter has a stable drift rate of less than 2% per year.
  • MADE IN THE USA: All meters are designed, built, and calibrated at our headquarters in Logan, Utah, USA. Apogee Instruments has been creating research-grade instruments for scientists and serious growers for over 25 years. All meters are backed by our industry leading four-year warranty and supported by our world-class, US-based customer support team.

Package Dimensions ‏ : ‎ 4.69 x 4.33 x 2.32 inches; 6.38 Ounces


Batteries ‏ : ‎ 2 AAA batteries required. (included)


Date First Available ‏ : ‎ February 1, 2022


Manufacturer ‏ : ‎ Apogee Instruments


Best Sellers Rank: #142,166 in Patio, Lawn & Garden (See Top 100 in Patio, Lawn & Garden) #677 in Plant Growing Lamps


#677 in Plant Growing Lamps:


Customer Reviews: 4.5 4.5 out of 5 stars 14 ratings


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Sep 27

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Can't beat the accuracy and reliability of Apogee products
Style: DLI-600
If I had to force a complaint I'd say I wish I didn't have to remove 2 screws to access the USB-C port, but I have no doubt it's concealed where it is for a reason, and it's not much of an inconvenience at all. Otherwise it's all positive marks for the DLI-600. The universal thread is a great idea, I picked up an inexpensive, telescoping tripod/wand to use for quick and long term readings. Compared these readings with a 2 year old MQ-510 and they're nearly identical. Easy to access the files via the included USB-C cable on my laptop. You get what you pay for and I have no doubt this DLI-600 will be taking accurate readings for years to come. No more burning, or under lighting my plants. Keep up the good work, Dr. Bruce. ... show more
Reviewed in the United States on October 21, 2022 by Larry Larry

  • Broken From Bad Design
Style: DLI-600
The battery compartment screw was completely stripped and the screw falls out. It arrived like that. Incredibly poor design for an expensive instrument.
Reviewed in the United States on May 26, 2023 by John Falmore

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