Metrohm 840 PC Control 5.0 / Touch Control - Manual (Page 235)

4 Parameters
PC Control / Touch Control
223
4.1.5 Control device, sensor, dosing device and stirrer
Under Control device you can select the Titrando or the Robotic Ti-
trosampler with which the titration (or measurement or calibration) is to
be carried out. This button will only appear when several control de-
vices that are able to execute the corresponding command have been
configured under System/Device manager (see Section 3.10). The in-
strument names are always shown in the selection list.
The parameters for the electrode connection are edited under Sensor:
• Measuring input (d): Selects the measuring input to which the
sensor is connected. The choice is not dependent on whether the
Titrando has one or two measuring inputs.
• Sensor (d): Selects the sensor from the sensor list defined under
System/Sensors . The selection depends on the quantity to be
measured (see online help). You can also enter a sensor name
which is not contained in the sensor list. However, the sensor must
be present in the sensor list when the determination is carried out.
• I(pol) (d): The polarization current is the current applied to the po-
larizable electrode during a voltametric measurement. This parame-
ter is only available for I(pol) titrations/measurements.
• U(pol) (d): The polarization voltage is the voltage applied to the po-
larizable electrode during an amperometric measurement. This pa-
rameter is only available for U(pol) titrations/measurements.
• Electrode test (d): The electrode test for polarizable electrodes is
carried out during the transition from an inactive condition to a
measuring condition. A check is made that the electrode is properly
connected and that no short-circuit is present.
• Temperature measurement (d):
The temperature is normally measured automatically if a tempera-
ture sensor is connected. Otherwise the temperature entered
manually under Temperature (Titration/Measuring/Dosing parame-
ters) will be used.
With continuous you can ensure that a temperature sensor must be
connected.
With off the temperature entered manually under Temperature will
always be used. In case of electrode calibration and the electrode
test, the temperature is requested after the start, except the deter-
mination is carried out with a Sample Processor.
The parameters for the dosing device are edited under Dosing device:
• Dosing device (d): Selects the dosing device to be used for the ti-
tration. All the dosing device connections (MSB) are always shown.
• Titrant (d): Titrant to be used for the titration (or dosing). The ti-
trant can be selected from the list of titrants which have been de-
fined under System/Titrants. If intelligent exchange or dosing
units are used then a check will be made in the method sequence
that the correct titrant is present in the connected dosing device
and whether the type of dosing device is correct. With non-
intelligent exchange or dosing units the cylinder volume is checked.