Elcometer 138 Guia Del Usuario página 8

4 USING THE CONDUCTIVITY METER (continued)
4.5 SELECTING THE MEASUREMENT RANGE
The Elcometer 138E can be set to limit the reading to a particular
measuring range (PU, LO or HI) or full scale (AUTO). The default
setting is AUTO.
Measuring Range &
Resolution
When a range other than AUTO is selected, the meter can be
calibrated only for that particular range. If a sample is measured which
has a higher conductivity level than the selected measuring range, the
error message 'OR' is displayed.
To select the measuring range (Figure 3):
1 With the meter switched off, press and hold the '°C/°F' button,
then switch the meter on. Release the '°C/°F' button.
2 The meter goes into range selection mode. The currently
selected range is shown in the lower display. The upper display
shows the maximum possible reading for the selected range.
Press 'HOLD ENT' repeatedly until the required range is
displayed (PU, LO or HI).
3 The meter automatically conrms the last selection if no button is
pressed for 5 seconds. The upper display momentarily shows
'CO'. The LCD shows the power-up sequence and the meter
goes to measurement mode.
°C/°F
Auto conrmation occurs for the last selected range if no key is pressed for 5 seconds.
en-7
R
PU:
LO:
HI:
Figure 3: Selecting the Measuring Range
HOLD
ENT
0 - 200.0µS/cm
0 - 2000µS/cm
0 - 20mS/cm
HOLD
ENT
0.1µS/cm
1µS/cm
0.01mS/cm
HOLD
ENT
Power-up
Sequence
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