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URS20SI_en.doc - rev. 0
Oxygen detectors – URS20SI
20/10/2010
Gas detection systems for industrial environments
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Sensors lifetime
Sensor average lifetime (see technical characteristics) is referred to a typical usage
in a pollution-free environment. Presence of a high concentration of pollutants can
shorten the lifetime of the sensing element.
Once the detection system starts up, it has to be supplied with energy during all the
lifetime of its sensors.
Seasonal use of the detection system is not recommended.
Installation
Oxygen excess
Since oxygen weighs more or less the same as air, unless there is forced or natural air
circulation, it tends to spread at the point of the leak.
So, the excess oxygen detectors must be installed near any likely leakage points, in
order to detect the excess oxygen as quickly as possible.
Oxygen deficiency
Detection of oxygen deficiency has the purpose of indirectly detecting the presence of
other gases that deplete the oxygen in the air, therefore causing asphyxiation problems,
for example.
In this case, the detectors must be located at the breathing height of the occupants in the
premises.
Take into consideration the following specific installation guidelines, as well as the above
instructions, for location of the detectors.
The detectors must be installed:
1. where accidental gas leakages are possible
2. at least 1.5m away from heat sources or from vent holes
3. not in spaces where ventilation is poor and where gas pockets may form
4. away from hindrances to natural gas flow
5. away from equipment that may leak gas during normal operations
6. in environments with a temperature range of -20°C to 50°C and relative humidity
below 90% (non-condensing)
7. Disconnect equipment from the power supply when mounting and dismantling
detectors.
Special
recommendations
CAUTION:
safety is guaranteed only if cover is screwed on tight.
-
Tighten the cover clockwise, and when it is screwed on, make sure that
there is no more than 0.5 mm between housing and cover. This guarantees
that it is screwed on tight. Remember to tighten the hexagon locking grub
screw that fits into the end of the cover.
-
It is not essential to comply with the words << DO NOT OPEN WHEN
ENERGISED >>, since this product is suitable for use in non-hazardous
areas. In any case, make the area safe before opening the sensor cover.