beautypg.com

Metrohm 726 Titroprocessor User Manual

Page 166

background image

8.6 KFT

726 Titroprocessor, Instructions for use

160

160

buret cylinders; however, when the method is carried out

the dosing speed will automatically be reduced to the larg-

est possible value.

Pause 1

Delay before start of preliminary dosing

0 … 9999 s

Before the preliminary dosing is started a delay period can

be allowed to elapse. This can be used, for example, to en-

sure that a sample is completely dissolved in a solvent.

Pause 2

Delay before the start of the controlled titration

0 … 9999 s

Before the controlled titration is started a delay period can

be allowed to elapse. If a preliminary dosing has been car-

ried out then the delay period will start when the preliminary

dosing has been concluded. This option should be used

when a sample requires a certain reaction time in order to

start the titration reaction.

Extract. time

Minimum duration of a titration

0 … 9999 s

If a sample is difficult to dissolve it is recommended that an

extraction time is defined to ensure that a KFT titration is

not concluded until at least the extraction time has elapsed.

This means that if an endpoint is reached prematurely then

during the extraction time – if necessary – the preset meas-

uring value for the endpoint will continue to be held.

Titration conditions

These are the actual titration parameters which control the measurement re-

cording and the dosing behavior during the titration itself.

Direction

Direction of potential jump

pos. | neg. |auto

The direction of the alteration in the measurements is im-

portant for titration control in the KFT mode. Normally the

'neg.' setting should be used. The 'pos.' and 'neg.' set-
tings refer to the numerical measured value alterations. The

potential jump direction can also be determined automati-

cally. The potential jump direction is then obtained from the

initial measured value and the preset target endpoint.