Bosch ETT 008.31, Инструкции по ремонту

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6 Checking and fine-tuning measuring accuracy
!
Before commencing testing or fine-tuning work as described in Sections 6.2 or 6.3, the analyzer must be warmed up for a period
of 10 minutes. The cover of the device must be closed during this time.
It is essential to note the instructions in Section 6.1 before checking and fine-tuning measuring accuracy.
Please observe the propane factor of 0.5 for checking or fine-tuning the HC measuring channel.
Observe safety regulations when working with toxic gases.
6.1 Taking account of barometric altitude
Before checking or fine-tuning measuring accuracy, using a barometer read the current air pressure at the site in which testing or
adjusting is taking place.
In addition, find out what altitude is stored in the analyzer in input mode to Section 4.1.7.
If the analyzer is equipped with an air-pressure gauge (and this has been activated as described in Section 4.1.6), then check the
following:
- Does the altitude stored in the analyzer correspond to a mean air pressure which does not deviate by more than +50 mbar from the
currently measured air pressure? If there is a difference of 50 mbar or more, set the altitude in the analyzer to the current value.
If the analyzer is not equipped with an air-pressure gauge, the altitude in the analyzer must be set to the value which most accurately
corresponds to the current air pressure.
After you have finished checking or fine-tuning the device, set the altitude at which the device is to be used by the operator.
Altitude for mean air pressure
Altitude in m Mean air pressure
above sea
level
in torr in Hpa (mbar)
-700 825 1099
-600 815 1087
-500 806 1074
-400 797 1062
-300 787 1049
-200 778 1037
-100 769 1025
0 760 1013
100 751 1001
200 742 989
300 733 977
400 724 966
500 716 955
600 707 943
700 699 932
800 691 921
900 682 909
1000 674 899
1100 666 888
Altitude in m Mean air pressure
above sea
level
in torr in Hpa (mbar)
1200 658 877
1300 650 867
1400 642 856
1500 634 845
1600 627 836
1700 619 825
1800 611 815
1900 604 805
2000 596 795
2100 589 785
2200 582 776
2300 574 766
2400 567 756
2500 560 747
2600 553 737
2700 547 729
2800 539 719
2900 533 711
3000 526 702
6.2 Checking the indicating accuracy
The pump must be switched off. Select analysis mode with the "Select" button (press 10 x) and activate with the ”Enter
o
”
button.
Introduce a flow of test gas no. 4 into the device via the calibration-gas inlet.
Read the displayed values of the CO, CO
2
and HC measuring channels and compare with the certified test-gas values.
Maximum permitted indicating error = 5% from certified test-gas value.
If the value of one of the measuring channels exceeds the maximum permitted error, re-tune the measuring channel in ques-
tion to Section 6.3.