Xylem DO600 Dissolved Oxygen Meter - Manual (Page 4)

DO600 - Version 5.0 8/05 4
Calibration
1. Calibration should be performed on a daily basis.
2. Turn the meter ON
3. Press and hold the MODE/HOLD button until % is displayed on the LCD.
4. Allow the electrode to fully polarize. (readings are stable)
5. Place the electrode cap onto the electrode. The sponge contained in the cap should be
moistened (not soaked) with DI (distilled water) or clean tap water. Be sure that the
electrode membrane is clean and dry or the calibration will be incorrect. Never touch the
membrane, as skin oil will affect the electrode response.
6. Wait until the reading stabilizes then press and hold the CAL/RECALL button until CAL is
shown in the lower display. The readings will blink “101.7” and “SA” will appear.
7. When the calibration is complete “End” will appear and then the meter will return to the
normal measurement mode.
Note: The “SA” will not appear if the calibration fails.
8. Optional ’zero oxygen’ calibration: (improves measurement accuracy for very low or very
high DO measurements)
Place the electrode in a zero oxygen calibration solution, such as 5% sodium sulfite, wait
for stability and press the CAL/RECALL button until CAL is shown in the in the lower
display. Stability in a zero solution may take many minutes, depending on electrode
history.
Note : Sodium Sulfite can become deposited on the electrode and on the “coined” surface
of the electrode retaining collar. The presence of the Sodium Sulfite will negatively affect
future DO measurements until such a time where ALL of it is removed from the electrode.
Measurement Units
The meter can be set to measure % saturation, dissolved oxygen in mg/l, and dissolved
oxygen in parts per million (ppm). To change the mode:
1. Press and hold the MODE/HOLD button for 2 seconds and the display will begin to scroll
through the different units of measure :
% saturation; D.O. in mg/l; D.O. in ppm (parts per million)
2. When the desired units are displayed, release the MODE/HOLD button and the unit will
return to normal operating mode.
Note: The “HOLD” function cannot be on when changing the measurement function. If “HOLD”
is displayed in the lower left corner of the display, briefly press the MODE/HOLD button to turn
it off.
Temperature Units (ºF / ºC)
1. With the unit OFF, press and hold the CAL/RECALL button.
2. With the CAL/RECALL button depressed, momentarily press the ON/OFF button to turn
the unit ON.
3. The CAL/RECALL button can be released when ‘Self Cal’ is shown in the display.
Salinity Compensation
1. With the unit ON, momentarily press the CAL/RECALL button twice in quick succession
(‘SAL’ is shown in the lower temperature display).
2. Momentary press the MODE/HOLD button. Each press of the MODE/HOLD button
increases the compensation by 1ppt (part per thousand); the available range is 0 to 50ppt.
3. Momentarily press the CAL/RECALL button to save the compensation setting and return
to the normal measurement mode.