Specifications

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Instruction 0019-9208
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O Monitor 3010
2.3 Start-Up Display
The display that appears when the monitor is fi rst turned ON de pends on
what Time Weighted Average mode the monitor is currently in, and how
long the monitor has been OFF. Refer to Section 2.6 Time Weighted Aver-
age (TWA/twa) Mode.
If the mon i tor is in its 8-hour ‘TWA’ mode and was OFF for more than
8 hours, then the fi rst display appears at turn-on, which iden ti fi es the
mon i tor and shows the count down of the monitor’s 30 minute warm-up
period. After the warm-up period expires, the monitor au to mat i cal ly starts
a new TWA reading. But if the mon i tor was OFF for less than 8 hours,
then the second display appears, which gives an op er a tor the option of
con tinu ing the pre vi ous TWA reading by press ing the f2 button.
If the monitor is in its continuous ‘twa’ mode, then the second display
always appears at turn-on, again giving the operator the option of con-
tinu ing the pre vi ous continuous twa reading.
If f2 is pressed, then the monitor continues operation with the pre vi ous
TWA/twa. But if f2 is not pressed during warm-up, or if one of the other
func tion buttons is pressed, then the mon i tor au to mat i cal ly starts a new
TWA/twa reading. At this time the monitor reverts to the fi rst display for
the re main der of the warm-up period.
2.4 Response Time
The 3010 monitor measures very low levels of N
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O. To obtain this high
sensitivity the detected gas level is averaged over a reasonable length of
time. The displayed value is an average over the previous 40 seconds and
is updated every second. Response time is measured by the parameter
T90, which is the amount of time it takes the monitor to reach 90% of the
true value. T90 for the 3010 monitor is 90 seconds, which means if 80 ppm
test gas is applied to the monitor it would take it 90 seconds to reach a
reading of 72 ppm (90% of T90). To get the most accurate reading, the
monitor should be turned ON for a minimum of 3 minutes before taking a
measurement.
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