E Instruments E4500, Руководство по эксплуатации и техническому обслуживанию

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When auto-calibration is complete the instrument will instruct the user to insert the sample probe that has been
previously connected to the relative input on the instrument, and the analysis screen will appear automatically.
In order for the probe to be inserted at the right point within the stack, its distance from the boiler has to be twice
the diameter of the stack pipe itself or, if this is not possible, must comply with the boiler manufacturer’s
instructions.
In order to position the probe correctly, a reliable support must be provided by drilling a 13/16 mm hole in the
manifold (unless already present) and screwing in the positioning cone provided with the probe - in this way no air
is drawn from the outside during sampling.
The screw on the cone allows the probe to be stopped at the right measuring depth - this usually corresponds to
the center of the flue pipe. For greater positioning accuracy, the user may insert the probe gradually into the pipe
until the highest temperature is read. The exhaust pipe must be inspected before carrying out the test, so as to
ensure that no constrictions or losses are present in the piping or stack.
13.1.3 Flue Gas Analysis
After the sample probe has been inserted in the stack and the combustion air temperature probe (if used) has
been inserted in the relative sample manifold, if the instrument has not been configured during auto-calibration,
the following data must be configured:
Memory: use this submenu to define the memory in which the test data and client details are to be stored.
Fuel: the user will be asked to define the type of fuel used by the plant.
Operator: this is where the name of the test operator can be entered.
Mode:
by entering this submenu, the user can determine the analysis mode - manual or automatic.
If automatic mode is chosen, the reading duration of each and every test must be set, besides the printing mode -
manual or automatic. When flue gas analysis begins, the instrument will perform and memorize the three tests
automatically, at the respective intervals set (at least 120 sec. according to UNI 10389-1).
At the end of each test the instrument will emit an audible alarm (one "beep" after the first test, two "beeps" after
the second test and three "beeps" after the third test).
At this point, when all three tests are over, if "Manual Printing" has been chosen the instrument will display the
average of the three tests with the possibility of recalling the individual values.
If desired, the user can then print the relative data (total, complete, etc....). On the contrary, if "Automatic Printing"
was selected, the instrument will print the test data automatically, based on the current print settings, without
displaying the average test values.
Caution: when in automatic mode Draft, Smoke and ambient CO (NO) measurements must be taken
before initiating the flue gas analysis.
If, on the other hand, manual analysis mode is chosen, flue gas analysis will proceed manually (please see
relative Flow Chart). In this case the print settings and automatic test duration will not be considered.
At this point manual analysis may commence, first waiting at least two minutes until the displayed values
stabilise: The user can then proceed with data storage, if required, or print the analysis report directly.
The latter will be printed in the format set beforehand.
When all three tests are over, the user can recall the average analysis screen containing all the data necessary
for compiling the maintenance log of the boiler or plant.
In both modes, automatic and manual, the displayed data of the pollutants CO / NO / NO
x
can be translated into
normalised values (with reference to the concentration of O
2
previously set).
13.1.4 End of Analysis
At the end of the combustion analysis, carefully remove the sample probe and remote air temperature probe, if
used, from their relative ducts, taking care not to get burnt.
Switch off the instrument by pressing the On/Off key.
At this point, if the instrument has detected a high concentration of CO and/or NO, a self-cleaning cycle will be
initiated during which the pump will draw fresh outside air until the gas levels drop below acceptable values.
At the end of the cycle (lasting no longer than 3 min.) the instrument will switch itself off automatically.