Metrohm 840 PC Control 5.0 / Touch Control - Manual (Page 278)

4.9 Electrode test for pH electrodes (ELT)
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PC Control / Touch Control
Under Electrode test parameters you can edit the parameters for
the electrode test sequence.
• Buffer type: Selects a predefined buffer series for the calibration.
The following buffer series are available: Metrohm, NIST, DIN, Fluka
Basel , Mettler, Merck Titrisol, Radiometer, Merck CertiPUR,
Baker , Hamilton, Precisa. The temperature tables for the buffer se-
ries can be found in Section 6.4.
• Sample Processor: If the calibration is carried out with a Sample
Processor then the buffers are changed automatically. That is why
there is no request of the calibration temperature at the start of the
calibration. The value entered below is used.
For calibrations with a Sample Processor connected via a remote
box the parameter Remote must be activated. When the measure-
ment of a buffer has been completed the Titrando sends a signal to
the Sample Processor via the remote connection (EOD, see Sec-
tion 6.2.2). The Sample Processor then switches to the next buffer.
For automatic calibrations with the USB Sample Processor the pa-
rameter USB must be selected. The CAL command must be called
up in a subsequence (see Section 4.12.6) with the subsequence
option "Cycles = Calibration". In order to change the calibration
solution a MOVE command (see Section 4.12.1) must be inserted
before the CAL command with the target "Calibration pos.". The
1st calibration position must be defined in the rack table (see Sec-
tion 3.10.5) as a sample position or as special beaker. If a sample
position has been given as the 1st calibration position then it is es-
sential that the other calibration solutions are placed in the directly
following rack positions. If special beakers are used for the calibra-
tion then there must be as many special beakers defined as buffers
or standard solutions are required for the calibration. The special
beakers do not need to be placed in rack positions that directly fol-
low each other.
• Electrode type: Select the electrode type.
Standard : Electrodes containing, e.g., KCl solution as reference
electrolyte.
Gel
: Electrodes containing Idrolyte as reference electrolyte.
Non-aqueous : Electrodes containing a non-aqueous reference elec-
trolyte, e.g. TEABr in ethylene glycol or LiCl in ethanol.
Custom
: Under System/Templates you can define your own elec-
trode type.
• Temperature: Manually entered calibration temperature. If a tem-
perature sensor is connected and temperature measurement is set
to automatic or continuous under Sensor (see Section 4.1.5) then
the temperature will be measured. If off is defined then the tem-
perature is requested after the start (except the calibration is carried
out with a Sample Processor).
The parameters for Control device, Sensor and Stirrer are de-
scribed in Section 4.1.5.