LaMotte Tracer Dissolved Oxygen Meter - Manual (Page 11)

MODE/HOLD button. If there is no data stored in the memory, “END” will
be displayed briefly and the meter will return to the previous mode.
Clearing Stored Memory
Turn the TRACER on. Press and hold the ON/OFF button for 4 seconds.
The display will briefly display “clr” when the memory has been cleared.
Disable Auto Power Off
The auto-power off feature will automatically shut the meter off 10 minutes
after the last button was pressed. To disable the auto-off feature:
1. Press the ON/OFF button to turn the meter on.
2. Wait for the SELF display screen to appear. This is the second screen to
appear after turning on the meter. IMPORTANT: Review the
instructions for the next 3 steps before proceeding. Step 3 must be
followed immediately by Step 4.
3. Press CAL/RECALL button once.
4. Press MODE/HOLD and ON/OFF buttons simultaneously until oFF is
displayed on the screen. Watch carefull. It will disappear quickly.
5. To re-enable the auto-off feature, turn the meter OFF and then turn the
meter ON.
6. The auto power off feature will be restored automatically when the
meter is turned off. Auto-off is the default function when the meter is
turned on.
Calibration
Calibration should be performed daily. The electrode membrane must be
clean and dry or the calibration will be incorrect. This is a water saturated
air calibration.
1. Press the ON/OFF button to turn the meter on.
2. The meter must be in the % saturation mode. If the meter is not in the
% saturation mode, press and hold the MODE/HOLD button to change
to the next unit of measure in the sequence:
l % saturation
l dissolved oxygen, mg/L
l dissolved oxygen, ppm
Release the MODE/HOLD button when % saturation is displayed.
3. Observe the % saturation reading on the display. Wait until the reading
is stable.
4. The electrode membrane must be clean and dry or the calibration will
be incorrect. Moisten the sponge in the electrode storage cap with
distilled or tap water. The sponge should be moist but not soaked. Place
the electrode storage cap on the meter.
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