Apogee Instruments SQ-520 - Sensor PAR/PPFD

The Sonda SQ-520 can be connected directly to a computer via USB cable for point or graph and protocol measurement of PPFD(photosynthetic photon flux density = amount of PAR received by the plant from lighting) in real-time using the included software. It can also serve as a standalone protocol unit by simply connecting to a standard 5 V DC USB adapter. The internal memory inside the probe has a capacity of 10,000 user-specified periodic measurements with the option to save in CSV format.

Usage

• measurement of incoming PPFD.Unlike traditional LUX meters, it can be used for measuring LED lighting, where PAR and PPFD are crucial!

• Key Features

  ✔ Full-Spectrum PAR Detection (400-700 nm)

  • ±5% measurement accuracy (all light sources)

  • Blue-enhanced silicon photodiode

  ✔ Dual-Output Versatility

  • Analog (0-2.5V) and digital (MODBUS RTU) outputs

  • Compatible with most data loggers

  ✔ Rugged Field-Ready Design

  • Anodized aluminum body with acrylic diffuser

  • IP68 waterproof rating (submersible)

  • 2m armored cable (UV-resistant)

  ---

  Technical Specifications

  Optical Performance:

  • Range: 0-4,000 μmol/m²/s

  • Cosine Correction: ±2% at 75° zenith

  • Spectral Error: <5% (LED), <3% (sunlight)

  Physical:

  • Dimensions: 24mm diameter × 27mm height

  • Weight: 90g (sensor only)

  • Cable: 2m, 4-conductor shielded

  Environmental:

  • Operating Temp: -40°C to +70°C

  • Calibration Drift: <2%/year

  ---

  Included Components

  ✓ SQ-520 sensor head
  ✓ 2m waterproof cable
  ✓ NIST-traceable calibration certificate

  Optional Accessories:

  • Handheld meter (MI-200)

  • Data logger interface kits

  ---

  Professional Applications

  • Greenhouse light mapping

  • Vertical farm PPFD optimization

  • LED grow light validation

  • Photobiology research

  Calibration Interval: 2-year recommended