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Battery Replacement
The procedure for replacing the Reader Unit batteries is as follows:
5.
Turn off the instrument and place the Reader Unit face down on a clean dry
table and remove the four stainless steel retaining screws under the front panel
flange.
6.
Turn the unit upright and lift the front panel from the body of the Reader Unit
and place it face down on the lid. Unplug the battery lead connector (the one
with red and black wires) on the printed circuit board.
7.
Unscrew the battery carrier retaining screw (the one in the centre of the battery
pack) and remove the battery carrier.
8.
Take out the old batteries and replace with eight new "C" size batteries
positioned with the "-" terminals against the spring connectors of the battery
pack.
9.
Place the battery carrier in the Reader Unit and tighten the retaining screw. The
screw must be firmly secured so that the batteries do not move during
deployment of the instrument.
10.
Make sure that the rubber gasket on the Reader Unit lid and the surfaces in
contact with it are clean.
11.
Replace the printed circuit board connector making sure that it is pushed firmly
in place. The connector will only fit if it is oriented correctly.
12.
8. Replace the front panel and the four retaining screws, making sure that you
tighten them firmly in a diagonal pattern.
D.O. Sensor Maintenance
To maintain the performance and accuracy of the dissolved oxygen sensor, the
membrane should also be replaced if it becomes damaged or contaminated with organic
matter. Clean the membrane with cotton wool saturated with alcohol