Bacharach Gas Pup, Инструкция

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Gas Pup
12 Instruction 55-9002
After checking for gas, allow the instrument to sample fresh air until the
LCD shows a very low ppm reading. This will help prolong sensor life by
purging the sensor chamber of combustible gas.
Auto-Ranging
The Gas Pup incorporates an auto-ranging
function that automatically switches the
display between ranges when a range limit is
reached. This avoids manual switching, and
assures, in conjunction with the range display,
that accurate readings are provided at all
times. The range selected by the instrument is
indicated by a pointer that appears in the
RANGE window (see Figure 7).
When a reading in the PPM range exceeds
2,500 ppm (equal to 0.25% by volume, bar
graph at full scale), the display will automati-
cally switch to the LO% range, covering from
0.2% to 5.0%. This change will be instanta-
neous. But if the reading is close to 2,500 ppm,
observe that the display may flicker between
ranges for a few seconds.
When the LO% reading exceeds 5.0%, the
display automatically transfers to its HI% range. This transfer takes a
few seconds to allow the detector to stabilize in the new range.
Auto-ranging from HI% to LO% occurs when the reading falls below 5.0%
for more than 5 seconds. The 5-second delay is to prevent nuisance range
transfers.
Fixed HI% Range
Manual selection of the HI% range may be
made to avoid any delay caused by auto-ranging
(for example in barhole testing), and to retain
the highest reading shown on the bar graph. To
lock the instrument in its HI% mode, momen-
tarily press the
key. Once auto-ranging has
been overridden, the instrument will remain in
the HI% range until the
key is pushed again.
Operation
HI%
LO%
PPM
RANGE
HI%
LO%
PPM
RANGE
HI%
LO%
PPM
RANGE
PPM Range
LO% Range
HI% Range
Figure 7.
Range Display
HI%
LO%
PPM
RANGE
HI% Range
Figure 8.
Fixed High Range