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Ref. No. [UMCES] CBL 2015-008
ACT VS15-01
15
RESULTS of LABORATORY TEST
Instruments were tested in an extensive 10 week long laboratory tests under tightly controlled
temperature and salinity conditions to examine measurement accuracy, precision, and reliability.
Temperature and salinity conditions were maintained within large (4.5m
3)
storage tanks and the
water was constantly circulating into the instrument test tank (0.8 m
3
) except during sampling
timepoints (Photo 1).
Photo 1.
A. The two main source water tanks (4.5 m
3
) used to maintain specific salinity and temperature
conditions for each trial of the laboratory test. Water was continuously circulated between the source
tank and the instrument testing tank in between sampling timepoints. B. Test instruments being deployed
in the test tank (750 L). Water was continuously circulated internally within the tank during sampling
events. The shown PVC pipe served as the sampling stream inlet and was diverted directly into the
laboratory for reference sample withdrawal. Water returns to the test tank at a bottom opening below the
sensors. C. Fully instrumented test tank with all company instruments, reference thermistors, and
reference pH electrodes. Foam blocks were floated on the surface to minimize evaporation and help
maintain temperature set points. D. Laboratory set-up for the dye-based spectrophotometric analysis of
pH. The diversion tube coming through the wall from the test tank was used to draw off reference
samples. A water bath was used to keep the cuvette cells at the same temperature as the test tank during
filling.
A
B
C
D