Buchi K-355, Operation Manual

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6 Operation
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K-355 Operation Manual, Version G
6 Operation
This chapter gives examples of typical instrument applications and instructions on how to operate the
instrument properly and safely.
WARNING
Risk of injury.
Never operate the instrument when glassware is damaged. •
WARNING
Sodium hydroxide, acid and lye are used for applications according to Kjeldahl. For this reason,
protective goggles must be worn at all times when using this instrument or working in its immediate
proximity.
NOTE
Close unused connections with plug caps.
If the connection for reagent 1 (pump) is used for the addition of strong acids (e.g. HCl), rinse the
pump with distilled water at the end of the day.
6 .1 Addition of chemicals
6 .1 .1 Manual dosage
When pressing “REAGENT 1” or “REAGENT 2” the connected reagent is dosed as long as the switch
is pressed.
6 .1 .2 Automatic dosage
The reagent volume dosed before the distillation is started is stored (e.g. in one of the nine different
programs or as default value). This volume can be recalled after distillation (or a program containing
the required volume can be recalled).
The stored volume is dosed by pressing “REAGENT” shortly. After releasing the switch, the volume is
dosed automatically.
6 .1 .3 General information
The reagent switch is also active when the instrument is “Ready” or “Busy” (during distillation), so that
additional dosage of reagent is possible during distillation.
During preheating, reagent addition is not possible.
The reagent volume stored before the start of the distillation is defined as the pump operating time.
The stored pump operating time (reagent volume) can be recalled after the distillation or after pressing
“STOP”.
If “STOP” is pressed during the automatic addition of reagent, the default volume is set to 0 ml.
The pumps for addition of Reagent 1 and Reagent 2 are different. Therefore different settings for the
two pumps may be necessary.