MODEL 300 COMBUSTION ANALYZER
3-12
Instruction 24-9223
TABLE 3-1. Basic Error, Warning and Overrange Displays (Cont.)
Display
Shows
Display Meaning
Remedy
Allow thermocouple to stabilize at
room temperature and then recali-
brate the analyzer.
Adjust potentiometer R19. Refer to
Section 4.4.
Replace probe assembly, or replace
just the thermocouple. Use Fig. 5-4 as
guide when replacing just the thermo-
couple.
Acknowledge and clear the overrange
by pressing the left SELECT key until
the left display shows either CAL or
RUN. The analyzer will then auto-
matically restart either its calibration
or run sequence. If a CO or O
2
over-
range condition reoccurs after two
attempts to clear it, purge the
analyzer’s gas sampling system by
removing and then reapplying power
to the instrument. Allow pump to run
5 minutes (longer if necessary) while
sampling fresh air. Then press CAL.
Error, thermocouple
temperature below –
100° or above 2300° F
(–73° and 1260° C).
Error, thermocouple
span potentiometer
R19 misadjusted.
Error, thermocouple
defective.
Overrange in CO
channel.
Overrange in ambient
channel.
Overrange in thermo-
couple channel.
Overrange in O
2
channel. O
2
CELL
indication rose above
74.4 mV during calibra-
tion cycle or during
normal operation.
E*TC
OR/C
OR/A
OR/T
OR/O
