Ametek CEM/Humox, Руководство пользователя

Страница: 56 / 136

4-12 | Thermox CEM/Humox Analyzer
System Serial #
This menu option allows you to view your system serial # and manufacturing #.
You may be asked by AMETEK/Thermox personnel to provide this information
upon request.
1. Select System Serial # from the Setup menu.
2. Select System Serial # or Manufacturing #.
3. The system displays the system serial # or manufacturing #.
Primary Calibration
The actual furnace temperature set point will vary from unit-to-unit based upon the
Primary Calibration which correlates the actual cell response for the desired 695°C
cell set point temperature with the actual furnace thermocouple feed back tempera-
ture. This is accomplished by applying two known concentrations of oxygen to the
analyzer during the primary calibration. The software algorithm then calculates the
actual cell temperature from the cell mV response and then makes the appropriate
increase or decrease in the furnace temperature control set point. If you take the
displayed cell temperature and divide it by the T/C Ratio in memory location 88,
then this is the actual furnace set point control temperature. If you take a Type-K
table, you should be able to measure the voltage on terminals C and D on the sensor
board, and then add the appropriate amount of mVs for the board ambient, your cor-
responding temperature from a Type-K thermocouple should be the actual furnace
set point temperature = 695°C / T/C Ratio (memory location 88).
Use the Type-K table to determine the mV change you have for 273°C and adding
this mV change for the actual board temperature, should be the compensation volt-
age measured between D+ and 6- on the sensor board. So for a 50°C ambient at the
board, the voltage should be 11.05 mV (273°C) + 2.02 mV (50°C) = 13.07 mVs.
If you have a T/C ratio of 0.9, the corresponding furnace temperature set point should
be (695°C / 0.9 = 772°C). If you measure the voltage at terminals C and D on the
sensor board with a 50°C ambient, the voltage should be 32.125 (772°C) - 2.02 mV
(50°C) = 30.1 mV. If you add in the compensation voltage for 50°C, the voltage at
terminals 5 and 6 should be 30.1 mV + 12.05 mV = 42.15 mVs which should also
be the voltage that you measures at T/C+ and T/C - terminals on the Series 2000
wiring card terminals and also the displayed T/C mV value that you can set one of
the display lines to view in the Setup key - Display menu.