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8.
When the reading has stabilised, press the
key to zero the Relative mV reading.
(a) If only one Channel is in Relative mV mode, the Relative mV reading will now be zero,
and the absolute mV reading will remain unchanged. In the following example, Channel 1
is in Relative mV mode, and Channels 2 and 3 are in Specific Ion and pH modes…
0.0mVR 10.0ppM 7.00pH 25.0
0.0mVR 10.0ppM 7.00pH 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
(b) If more than one Channel is in Relative mV mode, the
900-I3
will offer a choice of
Zeroing any one Channel, or all Channels. For example…
500.0mVR 500.0mVR 500.0mVR 25.0
500.0mVR 500.0mVR 500.0mVR 25.0
O
O
c
c
Zero F1:Chan1 F2:Chan2 F3:Chan3 F4:All
Zero F1:Chan1 F2:Chan2 F3:Chan3 F4:All
Press
,
,
or
according to your requirements.
9.
The
900-I3
Relative mV mode is now zeroed and is ready for use. The readout can be re-zeroed
by repeating the steps detailed above whenever required.
6.3 Relative Millivolt Calibration Notes
1.
Temperature compensation does not apply in Relative mV mode,
2.
The Relative mV offset is retained in memory when the
900-I3
is switched off, even when the
power supply is removed.
3.
The Relative mV zero offset for any one Channel is reset when leaving Relative mV mode for
that Channel.