Advertisement
Technical Note TN-151
24 hours before calibrating. We recommend calibrating whenever
a sensor is removed, even if the same sensor is reinstalled in the
same location.
FILTERS
It is good practice to replace filters at the same time a sensor is
replaced. Filters may need replacement more frequently if clogged
or saturated. Filter replacement is indicated when the sensor begins
to respond slowly or take a long time to recover from an exposure. In
addition to the instrument inlet filters designed to remove particles
and water droplets, some sensors (for example, CO) need other
external filters for proper operation.
• ToxiRAE membrane filter & MultiRAE/
QRAE filter cartridges. Replace when visibly
dirty or when sensor response become slow.
• CO sensor carbon filter. Replace when response to organic
vapors is noted or every six months, whichever comes first. This
filter is located in the MultiRAE, VRAE or QRAE cover plate.
• Remove the carbon filter if another sensor is used to
replace a CO sensor. For example, if an SO
is installed, the carbon filter removes these
gases and low readings are obtained.
Warning: Failure to remove the carbon filter
in the MultiRAE Plus cover plate for sensors
other than CO may result in low readings.
STORAGE
Sensors can dry out or burst if stored at very low or very high
relative humidity, respectively. To maximize sensor life, store sensors
and instruments indoors in a climate-controlled building. Note other
special conditions:
RAE Systems by Honeywell 877-723-2878 raesystems.com
02/08
or Cl
sensor
2
2
• Cl
sensors are particularly sensitive to high relative
2
humidity and may burst if stored in a refrigerator.
• Oxygen sensors are always on and are being consumed
by ambient air. These sensors are shipped in oxygen-
impermeable bags. The shelf life can be extended by k
eeping the sensor in the impermeable bag until it is used.
• Replace shorting springs on non-biased sensors
for rapid start-up when reinstalled.
• Store LEL sensors away from possible catalyst poisons
such as silicone-containing greases or rubbers,
sulfur compounds, and chlorine compounds.
• The plastic containers used to ship sensors are not
air-tight and do not provide long-term protection
from humidity extremes, O
BIAS SWITCH LOCATIONS
Nitric Oxide sensors should be placed in position 1 on the MultiRAE
and positions 1 to 3 on the VRAE. The MultiRAE Plus uses a jumper
moved from the right two pins to the left two pins to turn on the
bias. The VRAE uses three switches pushed up towards the sensors
to turn on the bias. The MultiRAE can have one biased sensor and
the VRAE up to three.
MultiRAE top view with c over plate removed showing location of
bias jumper and sensor positions.
, or LEL poisons.
2
2
Advertisement
