Apogee Instruments - SQ-640-SS: Quantum Light-Pollution Sensor

Brand: Apogee Instruments

The Apogee SQ-640-SS is a highly sensitive quantum light-pollution sensor (340 to 1040 nm) designed to detect the small light leaks during dark periods that can disrupt photoperiod-sensitive crops.

Stray photons during the dark period can trigger problems such as unwanted flowering response, hermaphroditism, and stunted growth. The SQ-640 is sensitive enough to find leaks the eye and standard PAR sensors miss. It is a specialty sensor that over-ranges under normal grow-light levels.

Key Features

• Extended range 340 to 1040 nm, optimized for low light
• Detects light leaks that disrupt plant dark periods
• Helps prevent hermaphroditism and photoperiod stress
• Analog, SDI-12, or microCache options
• Built and calibrated in Logan, Utah; NIST-traceable, made in the USA, and backed by an industry-leading 4-year warranty.

Why Choose This Model

The SQ-640 protects photoperiod integrity by finding the light leaks that cause costly crop problems.

Ideal Applications

• Dark-period light-leak audits
• Photoperiod-room commissioning
• Blackout and light-deprivation verification