Apogee MQ-500 Full Spectrum Quantum Meter

Ensure even more accurate measurement results

The MQ-500 quantum meter is the tool of choice for scientists all over the world to accurately measure photosynthetically active radiation from all light sources. It has a hand-held meter, attached via cable, that displays and stores measurements. The sensor incorporates a blue-enhanced silicon photodiode and custom optical filters with a rugged, self-cleaning sensor housing design, anodized aluminum body with acrylic diffuser.

The meter has a sample and log mode, and will record an integrated daily total in mol m-2 d-1. Sample mode will record up to 99 manual measurements. Log mode will power the meter 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, once full it will start to overwrite the oldest measurement with new ones. An integrated daily total will be recorded from the 48 averaged measurements (making a 24 hr period).

Sample and log measurements can be reviewed on the LCD display or by downloading the data to a computer, however, the integrated daily total can only be viewed by downloading the data to a computer. Downloading data to a computer requires the AC-100 communication cable (a standard USB cable will not work) and Apogee-AMS-Software.

Full-spectrum Quantum Sensor

Measure photosynthetically active radiation, PAR, in µmol m-2 s-1.

Apogee Instruments‘ quantum sensors provide accurate and cost-effective measurement of photosynthetically active radiation (PAR) from all light sources used to grow plants and corals.

Spectral Response

The full-spectrum quantum sensor has a spectral range of 389 to 692 ± 5 nm. The improved spectral response increases the accuracy of LED measurements.

Accurate, Stable Measurements

Sensors are cosine-corrected to maintain their accuracy when radiation comes from low zenith angles. The sensors measure PPFD with a cosine response accurate within ± 5 % at 75° zenith angle. Long-term non-stability determined from multiple replicate quantum sensors in accelerated aging test and field conditions is less than 2 % per year.

Typical Applications

PPFD measurements over plant canopies in outdoor environments, greenhouses, and growth chambers, and reflected or under canopy (transmitted) PPFD measurements in the same environments. Quantum sensors are also used to measure PPFD in aquatic environments, including salt water aquariums where corals are grown.

Rugged, Self-cleaning Housing

Patented domed shaped sensor head (diffuser and body) facilitate runoff of dew and rain to keep the sensor clean and minimize errors caused by dust blocking the radiation path. Sensors are housed in a rugged anodized aluminum body and electronics are fully potted.

Ideal for Measurements in Air and Underwater

Apogee quantum sensor are calibrated to make absolute PPFD measurements in air. The waterproof sensors can be used to make absolute PPFD measurements underwater by applying an immersion effect correction factor, the SQ-420, SQ-520, MQ-210, and MQ-510 already apply the correction factor. For details on making underwater measurements, please refer to Underwater PAR Measurements.

Calibration

To ensure accuracy each sensor is carefully calibrated in controlled conditions and traceable to NIST reference standards. The full-spectrum sensors are pre-calibrated for all light sources.

Mounting

The AL-120 Solar Mounting Bracket with Leveling Plate facilitates mounting the sensor to a mast or pipe. The AL-100 Solar Sensor Leveling Plate is designed to level the sensor while sitting an a flat surface or mounting to a surface.

Output Options

Available in multiple analog output option including 0 to 40 mV, 0 to 2.5 V, and 0 to 5 V. Additionally, a digital “smart“ sensor that uses USB cummunication and custom Software to interface directly to a computer is available. Sensors are also available attached to a hand-held meter with digital readout.

High Quality Cable

Pigtail-lead sensors feature an IP68, marine-grade stainless steel cable connector approximately 30 cm from the head to simplify sensor removal for maintenance and recalibration. Cable is shielded-twisted pair wire with a TPR jacket for high water resistance, UV stability, and flexibility in cold conditions.