2 performing a span calibration – stand-alone use – LumaSense Technologies INNOVA 1314i User Manual

Page 168

Advertising
background image

Chapter 12

______________________________________________________________________

_____________________________________________________________________________

BE6030-13

1314i Photoacoustic Gas Monitor

LumaSense Technologies A/S

Page 168 of 199

12.9.2 Performing a Span Calibration – Stand-alone Use

The general equipment necessary to perform a calibration task is

described in

section 12.4

. Follow the procedure from step 1 to step 3

inclusive and then continue as follows:

1.

a. Connect the free-end of the Teflon tubing mentioned in step 3

to the pressure valve on a cylinder of calibration gas.


b. Press

¿

.

c. Gently open the pressure-valve on the gas cylinder and

regulate the flow of gas so that when the Monitor’s pump is

running there is a positive flow of gas out of the flow meter.

This will ensure that the calibration gas is not diluted by

atmospheric air.

The following text appears on the screen:

RESULTS NOT YET AVAILABLE

PLEASE WAIT

Once the first measurement result is available the screen text

illustrated above is replaced by a screen displaying the

measurement results – for example the following:

W : µ : 5.34 µV σ : 212 nV 3 40.4 °C

PRESS ENTER WHEN RESULTS ARE STABLE

As soon as measurement results are available, they not only

appear on the display (see

Fig.12.12

) but are automatically

printed out on the printer, if the Monitor has been set up to print

a data log, see

section 10.5

. Remember to turn off the data log

when the calibration is complete.

Each time a sample of gas is drawn into the analysis cell the

signal is measured using both optical filter “A” and the water-

vapour filter (“W”) but, due to lack of space on the display, the

Monitor only displays the signal measured using the water-vapour

filter. The data-log print-out, however, shows the signal measured

using both the water-vapour filter and filter “A”. If cross-

compensation calibration was also selected in the calibration

set-up, then the signal is measured in the cell using all the

installed filters.

A maximum of 6 measurements are stored in the Monitor during

any calibration. The number (n) indicates how many

measurements are stored. When 7 measurements have been

Advertising