Features (ALW-CMP)
  • Small size, light weight & large memory capacity
  • High resolution
  • Non-volatile flash memory
  • Built-in calendar/time information
  • No PC interface required
  • Programmable calibration factors
  • Sensor wiper function
  • Proprietary cosine photo quantum sensor
  • Titanium housing
  • Easy-to-use data acquisition software (Windows version)
Photo sensor portion (ALW-CMP)

Compact-LW is a miniature and precision water-quality data logger with a micro-controller suitable for long-term deployment. Our updated state-of-the-art technology allows for a compact design capable of storing up to 179,178 sets of 2-channel data consisting of photo quantum and battery voltage.
The memory media, non-volatile flash memory IC's, protect data loss resulting from irregular battery voltage. This feature improves reliability.
Photo quantum sensor is developed by us and has the superior multi-spectral sensitivity characteristic and cosine characteristic.
A wiper keeps the sensor surface clean, which allows for up to one- month of continuous deployment.
Compact-LW is controlled through the PC serial port, RS-232C. The main unit records calendar and time information with each sample and the sensor's calibration coefficients are stored in the built-in memory. The basic measurement setup requires only the selections of the start time and the sampling interval.
The data transfer after the completion of the deployment is easily accomplished. Information, such as measurement start time and calibration coefficients are transferred together with the measured data.
The data processing program offers clear and logical screens for easy operation.
For profiling, AL30-CMPis available, in which depth and temperature sensors are equipped.

Parameter Photo quantum Photo quantum Depth Temperature
Type Photo-diode Photo-diode Semi-conductor Thermistor
Range 0 to 5, 000 µmol/s/m² 0 to 5, 000 µmol/s/m² 0 to 100 m -5 to 40 XC
Time constant 0.1 second 0.1 second 0.1 second 0.1 second
Accuracy Linearity 1 % Linearity 1 % 0.3 %FS 0.05 XC
Resolution 0.1 µmol/s/m² 0.1 µmol/s/m² 0.002 m 0.001 XC
Memory type 2 Mbyte flash memory
Capacity 179,178 data
A/D conversion 16 bit digital conversion
Interval 0.5,1,2,5,10,15,20 & 30 seconds
Burst time 1 to 1, 440 minutes, per step in minute
Sampling number 1,10,15,20,30,60,120,180,240,300,600 & 1200
Battery capacity Lithium battery 14 Ah Lithium battery 750 mAh
Power consumption 35 mA 39 mA
Material Titanium
Size 60 mm in diameter 170 mm in length
(Size of pressure case)
Weight 1,020 g in air & 510 g in water
Depth rating 200 m
Others With wiper function Without any wiper function (profiling)
Drawing (ALW-CMP)
Spectral Sensitivity and Cosine Characteristics