Cold Start; A/D Calibration - Novatech 1635 User Manual

5.1

COLD START

A 'COLD START' will reset all 'Set-up' mode entries to their factory default values. 'COLD START' will show on
the display for a second prior to a microprocessor initialising sequence, which takes about seven seconds. After a
'COLD START', it is necessary to set all new variables in the 'SET-UP' mode, including calibration voltages and time
and date.
To initiate a 'COLD START' -
Turn the mains power off
Remove the 'COLD START LINK' (this is located on the door PCB, next to the keyboard lock switch, behind the
shield)
Turn the mains power on. The message "Cold Start..." will be displayed on the lower line of the display.
Leave the LINK off until the message "Replace c/s Link" is displayed. Replace the LINK.
The date and version number of the software will be displayed.
A 'WARM START', which is performed by applying power with the COLD START LINK in its place, will retain all
data previously entered in the Set-up mode.
5.2

A/D CALIBRATION

The analyser maintains its accuracy over a long time by continuously checking itself against internal stabilised
references. The only calibration required is to set the actual values of these references into battery backed memory.
The analyser will read these references every minute and update its zero and span correction factors. See Section 4.5, 7
to 10.
These references should be checked every 12 months. An AUTOCAL of the analog output section should always be
performed if these references are altered. See Section 5.3.
Door Shield
46
ANALYSER MAINTENANCE
Reference voltage
test points.
Reference voltage
common point.
Location of Calibration Test Points
4
3
2
1
C
1630-1 PCB
16 Way
Ribbon Cable
40 Way
Ribbon Cable
August 2009
1635 Water Vapour Analyser