Metrohm 757 VA Computrace User Manual

Page 157

7.6 Standard addition technique

757 VA Computrace – Software

147

15. Enter the

Sample ID

(used as part of the determination file

name) in the

PLACE SAMPLE

window and click

16. Each time a standard addition is required in the

MANUAL AD-

DITION

window, add the standard addition solution using a

pipette.

Use manual standard addition with solution exchange

In the manual standard addition with solution exchange, a new
sample solution is used for every standard addition. Proceed as
follows:

1. Click on

MAIN WINDOW

/ Mode / Determination

2. Click on

MAIN WINDOW

/ Window / Working method

specification

to open the

WORKING METHOD SPECIFICATIONS

window.

3. Load the desired method into the

WORKING METHOD SPECIFI-

CATIONS

window (see How to load a method).

4. Select

Standard addition

in the

Calibration

field of the

WORKING

METHOD SPECIFICATIONS

window.

5. Select

Manual

in the

Addition

field of the

WORKING METHOD

SPECIFICATIONS

window.

6. Select

Batch with solution exchange

in the

Technique

field of the

WORKING METHOD SPECIFICATIONS

window.

7. Click

to open the

EDIT WORKING METHOD PA-

RAMETERS

window.

8. Select the

Determination

tab (see section 5.2) and enter

Sam-

ple identifier

Sample amount

Cell volume

, and the number of

spiked solutions in the

No. of cells

field.

9. Select the

Substances

tab (see section 5.2) and make sure

that for each substance entered in the table the concentra-
tions of the spiked sample solutions are defined in the

CELL

CONCENTRATIONS

window which is opened by clicking on the

button.

10. Close the

EDIT WORKING METHOD PARAMETERS

window by

clicking

11. Place the sample solution in the measuring vessel at the 757

VA Computrace Stand.

12. Click on

MAIN WINDOW

/ Window / Monitor

to open the

MONITOR

window.