Measure photosynthetically active radiation (PAR)
Get accurate and cost-effective measurement of
photosynthetically active radiation (PAR) from all light sources
used to grow plants.
Use it absolutely everywhere
The SQ-521 is a full-spectrum quantum sensor that measures the
Photosynthetic Photon Flux Density (PPFD) in ?mol m-2 s-1 from a
field of view of 180 degrees. Get superior, continuous PPFD
measurements over plant canopies in outdoor environments,
greenhouses, and growth chambers, and reflected or under-canopy
(transmitted) measurements in the same environments.
Best full-spectrum sensor on the market
The SQ-521 PAR Sensor is so accurate, it's considered the best
sensor on the market for difficult-to-measure indoor environments.
It has an incredible spectral range of 389 to 692 nm ± 5 nm, which
means superior performance under variable sky conditions and
increased accuracy under LED and other artificial light sources.
Sensors are cosine-corrected to maintain their accuracy even when
radiation comes from low zenith angles. Each sensor is carefully
pre-calibrated for all light sources in controlled conditions and
traceable to NIST reference standards.
Rugged, self-cleaning housing
The SQ-521 PAR Sensor is designed with a patented domed-shaped
sensor head (diffuser and body) to facilitate runoff of dew and
rain. This keeps the sensor clean and minimizes errors caused by
dust blocking the radiation path. Sensors are housed in a rugged
anodized aluminum body, plus each sensor comes with a special
mounting bracket and leveling plate.
Easy setup. Easy data access.
The simple-to-set-up SQ-521 is plug and play with the ZL6 data
logger, which self-identifies each sensor and includes a tilt
sensor so you can see remotely if your quantum sensor is off level.
Get instant and continuous data from the cloud wherever you are.
See your data on computer, tablet or smartphone.
Quality-guaranteed
If you need high-quality, continuous PAR measurements over the
long term, the rugged SQ-521 PAR Sensor has got you covered. It's
backed by an industry-leading four-year warranty and is considered
a standard for simple, accurate indoor/outdoor PAR measurements.
Plus, it's compatible with ZENTRA Cloud for easy remote data
access, so you can see your data anywhere, anytime.
| Specifications |
Specteral Range
|
389 to 692 nm |
| Accuracy |
± 5nm |
Directional (cosine)
Response |
± 2 % at 45°, ± 5 % at 75° zenith angle |
| Response Time |
Less than 1 ms |
| Long-term Drift |
Less than 2 % per year |
| Calibrations and Conversions |
Sensors are calibrated for outside use
5.0 µmol m-2 s-1 per mV |
| Power |
None, self powered |
| Operating Environment |
-40 to 70 C; 0 to 100 % relative humidity; can be submerged in
water up to depths of 30 m |
| Cable Length |
5 m |
| Cable connector Types |
3.5 mm "stereo" plug |
| Sensor Dimensions |
30.5 mm diameter, 37 mm height |
| Data Logger Compatibility (not exclusive) |
ZL6 & ProCheck |
| Warranty |
One year, parts and labour |
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Labcell Limited
exclusively supply and support METER products in the UK &
Ireland.
Non UK/Ireland Customers, please contact METER Environment at:www.metergroup.com/environment/