FLIR Extech ExStik EC400 User Manual page 8

Measurement and Display Considerations
•
If the unit appears to be locked (display frozen). It is possible that the Data Hold mode
has been inadvertently accessed by pressing the MODE/HOLD button. ("HOLD" will
be displayed in the bottom left of the LCD.) Simply press the MODE button again or
turn the meter off and then on.
•
For maximum accuracy, allow sufficient time for the temperature of the probe to reach
the temperature of the sample before calibrating. This will be indicated by a stable
temperature reading on the display.
Calibration - Conductivity
Meter accuracy verification should be performed on a periodic basis. Once per month is
the recommended cycle for normal use. If calibration is required, a conductivity
standardizing solution must be obtained. The meter can be calibrated in any or all of the
three ranges. Standardizing solutions of 84µS/cm, 1413µS/cm or 12.88mS/cm
(12,880µS/cm) are used for the automatic calibration recognition procedure. No other
calibration values are permitted.
Calibration is always done in conductivity mode. Since salinity and TDS values are
calculated from conductivity values, this procedure also calibrates the salinity and TDS
ranges.
1. Fill a sample cup with the standardizing solution.
2. Turn the meter ON and insert the electrode into the solution. Tap or move the
electrode in the sample to dislodge any air bubbles.
3. Press and hold the CAL/RECALL button (approximately 2 seconds) until "CAL"
appears in the lower (temp) display. The main display will start flashing.
4. The meter will automatically recognize and calibrate to the standardizing solution.
The display will briefly indicate "SA", "End" and then return to the measurement
mode after a calibration.
Note: The "SA" will not appear if the calibration fails.
5. The "range calibrated" symbol will appear in the display for each range that is
calibrated during that power on cycle.
Low range, 84µS/cm
Medium range, 1413µS/cm
High range, 12.88mS/cm (12,880µS/cm)
Note: Each time the calibration mode is entered all calibration symbols on the display are
cleared, but only the calibration data for the currently calibrated range is replaced. The
other two ranges keep the existing calibration data, just the symbols are removed.
Calibration of all three ranges must be performed during one power on period for all three
range calibration symbols to appear.
Note: The meter allows for a 1, 2 or 3 point calibration. If calibration is done for more than
one point the lowest value standard should be done first to obtain the best accuracy.
EC400-EU V2.2 8-11-05
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