Metrohm 840 PC Control 5.0 / Touch Control User Manual

Page 235

Parameters

PC Control / Touch Control

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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.