The underwater quantum sensor is typically used in salt water aquariums where corals are grown. Note: The handheld meter is not waterproof, only the sensor and cable are waterproof.

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 ApogeeAMS software.

Specifications
Calibration Uncertainty ± 5 %
Measurement Range 0 to 4000 µmol m-2 s-1
Measurement Repeatability Less than 0.05 %
Long-term Drift (Non-stability) Less than 2 % per year
Non-linearity Less than 1 % (up to 4000 µmol m-2 s-1)
Response Time Less than 1 ms
Field of View 180°
Spectral Range 389 to 692 nm ± 5 nm ( wavelengths where responsis greater than 50 %)
Spectral Selectivity Less than 10 % from 412 to 682 nm ± 5 nm
Directional (Cosine) Error Less than ± 5 % at 75° zenith anglean 10 % from 412 to 682 nm ± 5 nm
Azimuth Error Less than 0.5 %
Tilt Error Less than 0.5 %
Temperature Response -0.11 ± 0.04 % C-1
Uncertainty in Daily Totals Less than 5 %
Detector Blue-enhanced silicon photodiode
Housing Anodized aluminum body with acrylic diffuser
IP Rating IP68
Operating Environment 0 to 50 C; less than 90 % non-condesing relative humidity up to 30 C; less than 70 % non-condensing relative humidity from 30 to 50 C; separate sensors can be submerged in water up to depths of 30 m
Meter Dimensions 126 mm length; 70 mm width; 24 mm eight
Sensor Dimensions 24 mm diameter; 37 mm height
Mass 180 g
Cable 2 m of two conductor, shielded, twisted-pair wire; addititonal cable wire available; santoprene rubber jacket