0024-9551
Revision 1
35
PCA
®
400 User Manual
IMPORTANT
:
The PCA
®
400 performs a zero function during warm-up. Among
other purposes, an auto-zero determines the “zero reading” of the CO channel in
fresh air and provides an offset for the CO measurement. A manual zero detects
background CO during startup.
IMPORTANT
:
Both methods for zeroing CO require that the analyzer be turned ON
in fresh air; otherwise, incorrect CO readings will occur.
IMPORTANT
:
Both methods take the user through a 60-second count down to
establish a new zero. The manual mode establishes a fresh air zero and stores it for
use during instrument warm-up.
Fig. 4-2:
Gas Sensor Positions
Position 1
Position 2
Position 3
Position 4
Auto-Zero
When the CO channel is set to Auto-Zero, the CO sensor is zeroed to the ambient CO level
during start up.
Changing CO Zero Method
Auto-Zero determines the zero reading of the CO channel in fresh air and provides an offset
for the CO measurements. Manual Zero is used to detect CO that may be present during
start-up. The Auto / Manual Zeroing option allows the operator to select the start-up mode.
f
To change the CO Zero settings:
Main Menu
Settings
( )
CO Zero
select
Auto-Zero
or
Manual Zero
4.8 Sensor Setup
The PCA
®
400 is designed to allow sensors to be interchanged in the field; allowing users to
perform combustion tests for multiple gases with the same analyzer.
Changing Sensor Setup
f
To change Sensor Setup:
Main Menu
Settings
( )
Sensor Setup
select desired
sensor from dropdown menus
press
Save
( )
