Detcon CXT-IR - Manual (Page 9)

Model CXT-IR
The CXT-IR sensor utilizes a transceiver radio, based on the IEEE 802.15.4 standard. The transceiver operates
at 2.4 GHz using DSSS encoding for robustness in noisy conditions and to resist jamming. DSSS transmits
data across a wider frequency range than the actual frequency range required for the information. This
operation minimizes cross talk and interference from other transceivers and is less susceptible to noise from
other sources.
The IEEE 802.15.4 defines 16 separate RF Channels that can be used in the 2.4 GHz range. The default
channel is 1 but can be changed if there is RF interference or if there is an existing network using that channel.
Transceivers will only respond to other transceivers with the same RF Channel.
NOTE
If there are multiple CXT-IR networks in the same vicinity, each system must reside on a
different RF Channel to keep data from one appearing on the other system.
The 802.15.4 standard also implements a mesh network allowing any CXT-IR transceiver to relay or repeat
data between adjacent neighbors. This makes the network very robust and provides the following immediate
benefits.
• Allows re-routing of data in case of loss of a transceiver
• Allows re-routing around wireless obstacles
• Longer distances between transceivers because data can “hop” from one transceiver to the next
• Included in sensor, controller and alarm station transceivers
• CXT-IR transceivers can be deployed with less concern about physical location
1.4 Battery Pack Options
The CXT-IR can be powered by a battery pack that enables the IR to be remotely mounted without the need
for external cabling. Detcon offers several battery pack options that are factory installed. Contact Detcon for
more information on these options.
1.4.1
Detconꞌs Smart Battery Pack
The Detcon’s plug-in Smart Battery Pack provides an output of 12VDC (See Figure 7). The CXT-IR monitors
the battery pack for remaining battery life.
The battery pack consists of rechargeable Lithium-Ion batteries
and is equipped with integrated safety electronics that include fuel gauge, voltage, current and temperature
monitoring circuits. This “smart” circuitry continuously monitors the battery’s condition and reports critical
status information to the wireless transceiver via the Modbus™ registers. The battery pack is designed to plug
onto an 8-pin Beau connector on a Terminal Board that the sensor is connected to. The battery Pack and
Terminal Board are housed in the Detcon Aluminum Condulet to protect them from exposure to outside
elements and still provide Class I Div 1, C, and D approvals. Operating periods before recharge will vary
based on sensor attached, but can be as long as 5-6 months and battery life can be up to 5 years before battery
pack replacement is required. Improper use of the battery pack may be hazardous to personnel or the
environment and will void the warranty.
CXT-IR Instruction Manual Rev. 1.6 Page 5 of 44