Detcon IR-700 - Manual (Page 11)

Model IR-700
IR-700 Instruction Manual Rev. 3.1 Page 7 of 40
Although the sensor is designed to be RFI resistant, it should not be mounted in close proximity to high-
powered radio transmitters or similar RFI generating equipment.
When possible, mount the sensor in an area void of high wind, accumulating dust, rain, or splashing from hose
spray, direct steam releases, and continuous vibration. If the sensor cannot be mounted away from these
conditions then make sure the Detcon Harsh Environment Splashguard accessory is used.
Do not mount in locations where temperatures will exceed the operating temperature limits of the sensor.
Where direct sunlight leads to exceeding the high temperature-operating limit, use a sunshade to help reduce
temperature.
2.3 Sensor Contaminants and Interference
Detcon IR-700 combustible hydrocarbon gas sensors may be adversely affected by exposure to certain
airborne substances. Loss of sensitivity or corrosion may be gradual if such materials are present in sufficient
concentrations.
The performance of the IR sensor may be impaired during operation in the presence of substances that can
cause corrosion on gold plating. Other inhibiting substances are those that can coat the internal walls of the
optical chamber and reduce reflectivity. These include but are not limited to heavy oil deposits, dust/powder,
water condensation, and salt formation. Continuous and high concentrations of corrosive gases (such as Cl
2
,
H
2
S, HCl …etc.) may also have a detrimental long-term effect on the sensor’s service life.
The presence of such substances in an area does not preclude the use of this sensor technology, although it is
likely that the sensor lifetime will be shorter as a result. Use of this sensor in these environments may require
more frequent calibration checks to ensure safe system performance.
For the IR-700 Combustible gas sensors there are no known cross-interference gases that are not combustible
hydrocarbon gases.
For the IR-700 CO
2
Sensor, there are no known cross interference gases.
2.4 Mounting Installation
The IR-700 sensor assembly is designed to be threaded into a ¾” female NPT fitting of a standard cast metal
Explosion-Proof Enclosure or Junction Box. There are two wrench flats on the upper section of the sensor that
should be used to thread the sensor into the ¾” female NPT receiving connection. Thread the sensor up until
tight (5 turns is typically expected) and until the display is facing the direction that the sensor will normally be
viewed and accessed.
The IR-700 should be vertically oriented so that the sensor points straight downward. The explosion-proof
enclosure or junction box would then typically be mounted on a wall or pole. Detcon provides a standard
selection of junction boxes available as sensor accessories (See Figure 4 below), but any appropriately rated
enclosure with a downward facing ¾” NPT female connection will suffice.
When mounting on a wall, it is recommended to use a 0.25”-0.5” spacer underneath the mounting ears of the
Detcon standard J-Box to offset the sensor assembly from the wall and create open access around the sensor
assembly. Spacing requirements for other junction boxes may vary.
When mounting on a pole, secure the Junction Box to a suitable mounting plate and attach the mounting plate
to the pole using U-Bolts. (Pole-Mounting brackets for Detcon J-Box accessories are available separately.)