Zebra-Tech Ltd
D-OptoLogger Operation Manual
10
The D-Opto Logger will operate correctly until the battery voltage drops below
around 7.0 volts. If this occurs whilst the D-Opto Logger is in logging mode, the
last set of data values in the data file will be set to zero, and the D-Opto Logger
enters a low power sleep mode, with no further data values being logged.
Logging Interval
(minutes)
Memory Endurance (Days)
Standard D-Opto Logger
1 7
5 35
10 70
15 105
30 210
60 420
Table 1. Memory endurance
3.4 Routine
Maintenance
As with all instruments, it is good operating practice to make regular checks on
the quality of data being generated by the D-Opto Logger. This can be carried
out on site, using one of the following two methods:
1. Place a recently calibrated transportable dissolved oxygen sensor next to
the D-Opto Logger and compare the measurements. It is important to
allow a sufficient period of time for temperature equilibration to occur.
2. Place the D-Opto Logger in a solution of known dissolved oxygen content.
A solution of 0% dissolved oxygen saturation can be created by adding a
few teaspoons of sodium sulfite to 1 litre of distilled or fresh tap water.
The D-Opto Logger can tolerate some biofouling, however where possible steps
should be taken to minimise this; for example covering the D-Opto Logger can
reduce the amount of bio-growth by restricting available light. . The copper
biofouling control ring should reduce bio-growth in the area around the optical
window; this ring is sacrificial and may require replacement on an occasional
basis. Always use the nylon bolts supplied with the replacement ring to attach the
ring to the D-Opto Logger, and avoid over tightening.
Periodically it may be necessary to clean the D-Opto optical window, to remove
bio-growth or other accumulated deposits.
DO NOT
use a brush or any object
that may scratch or damage the optical window. Only use the cleaning pads
supplied with the D-Opto.