Ametek Thermox 2000 ATEX Series User Manual page 82

4-14 | Thermox Series 2000 WDG-HPII / HPIIC - ATEX
mary calibration and then attempt a standard calibration again. If you
get an excess cal error during primary calibration, then the furnace
temperature set point cannot be increased any further to prevent dam-
age to the cell housing and/or furnace assembly.
Failure limits for standard calibration -
+/- 10 mVs of the anticipated mVs for the gas concentration applied
(air 0 mV expected).
+/- 5 mVs of the anticipated mVs for the gas concentration applied
(2% O2 applied, 48 mV expected at 695°C cell temp) as referenced to
the actual span gas mV reading.
T/C ratio adjustment limits for Primary Calibration -
Cell Temp °C
615
650
695
824
790
For a cell operating temperature of 695°C, the T/C ratio low limit is .777
and the high limit is 1.222, which corresponds to a thermocouple indi-
cated temperature range of 540°C to 848°C.
If the analyzer is configured for a cell operating temperature of 695°C,
the highest possible operating temperature for the analyzer at after a
primary calibration is 848°C.
This menu option allows you to perform a primary calibration on the
zirconium oxide oxygen sensor. Perform a primary calibration on your
system rather than a regular calibration (from the Calibrate Key) in the
following cases:
When you replace your zirconium oxide oxygen cell.
When your system fails a regular calibration.
You should always attempt to perform a regular calibration before
resorting to a primary calibration for all cases other than when you
install a new cell.
NOTE
Max T/C Ratio
1.3
1.24
1.22
1.139
same as 824°C
Min T/C Ratio
0.7
0.74
0.777
0.861