46
MODEL SOLU COMP II
SECTION 8.0
TROUBLESHOOTING
5.
Calibrate the analyzer using the procedure in Section 6.3. Use 0.0 mV for Buffer 1 (pH 7.00) and -177.4 mV
for Buffer 2 (pH 10.00). If the analyzer is working properly it should accept the calibration. The slope should be
59.16 mV/pH and the offset should be zero.
6.
To check linearity, return to the main display and the pH/temperature/mV screen. Set the voltage source to the
values shown in the table and verify that the pH and millivolt readings match the values in the table.
8.4.3 Simulating pH input when the preamplifier is in a
junction box.
The procedure is the same as described in section 8.4.2.
Keep the connections between the analyzer and the junction
box in place. Disconnect the sensor at the sensor side of the
junction box and connect the voltage source as shown in
Figure 8-2.
8.4.4 Simulating pH input when the preamplifier is in
the sensor.
The preamplifier in the sensor simply converts the high
impedance signal into a low impedance signal without
amplifying it. To simulate pH values, follow the procedure in
Section 8.4.2.
8.5 SIMULATING TEMPERATURE
8.5.1 General.
The Solu Comp II accepts either a Pt100 or a Pt1000 RTD
in a three-wire configuration. See Figure 8-3.
Voltage (mV)
pH (at 25°)
295.8
2.00
177.5
4.00
59.2
6.00
-59.2
8.00
-177.5
10.00
-295.8
12.00
FIGURE 8-2. Simulating pH Input When the
Preamplifier is in the Sensor.
FIGURE 8-3. Three-Wire RTD Configuration.
Although only two wires are required to connect
the RTD to the analyzer, using a third (and some-
times fourth) wire allows the analyzer to correct for
the resistance of the lead wires and for changes in
the lead wire resistance with temperature.
