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6. Relative Millivolt Mode
6.1 Selecting Relative Millivolt Mode
Select Relative mV mode when measurements relative to a known standard are required.
Select relative mV mode for Channel 1, 2 or 3.
(e.g.
→
→
F3:Mode
F3:Mode
→
→
F1:Channel 1
F1:Channel 1
→
→
F2:mV
F2:mV
→
→
F2:Relative
F2:Relative
)
The
900-I3
will display the millivolt data relative to a known, user-selectable zero point.
Absolute millivolt data is also displayed for Channel 1 only.
6.2 Relative Millivolt Calibration
Calibration of the Relative mV mode is simply a matter of zeroing the reading when the sensor is in
the known standard.
1.
Plug the Redox sensor into the
Probe 1
,
Probe 2
or
Probe 3
socket. Temperature
compensation is not applied in Relative mV mode, so the temperature sensor does not need to
be connected.
2.
Switch the meter on.
3.
Select Relative mV Mode for Channel 1, 2 or 3.
(e.g.
→
→
F3:Mode
F3:Mode
→
→
F1:Channel 1
F1:Channel 1
→
→
F2:mV
F2:mV
→
→
F2:Relative
F2:Relative
)
4.
The display should now be showing Relative mV on the top line with absolute mV on the
bottom line. The following example shows all 3 Channels set to Relative mV. Note that the
Absolute mV reading is only displayed for Channel 1.
500.0mVR 500.0mVR 500.0mVR 25.0
500.0mVR 500.0mVR 500.0mVR 25.0
O
O
c
c
500.0mV F4:Zeros 31/12/98 12:00:00
500.0mV F4:Zeros 31/12/98 12:00:00
5.
Remove the wetting cap from the Redox sensor.
6.
Rinse the sensor in distilled water and blot dry.
7.
Place the Redox sensor into a sample of the known standard. Ensure that the platinum tip and
reference junction are both covered, as per the diagram below.