Engineering Documentation

Table Of Contents
Chapter 2 Network Electrical Systems
LONWORKS FLN Communications Wiring
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NOTE:
Sensor wiring (the wiring from the LTEC to the LTEC room temperature sensor) must
be included in the wire length calculations for a segment, because the sensor wiring
carries the network signal.
Fig. 36: Determining Network Length—Example.
Network Wiring
Only approved cables may be used for network wiring. These include unshielded and
shielded (where specified) to conductor 22 AWG Level IV cable.
WARNING
Use the recommended LonWorks cable: 22 AWG shielded or unshielded, Level IV
per NEMA standards (not equivalent to EIA/TIA Level 4 cable). Connect Air brand
cable, 22/1 pair, stranded, unshielded, blue plenum jacketed, Level IV, part number
W221P-2001, or an approved equal for network wiring.
Network wiring is NOT polarity sensitive.
LTEC Controllers use the FTT-10 transceiver that allows free topology wiring. This
includes
T-taps, stars, branches, loops, as well as standard daisy chain. In all cases, maximum
network wire length, including each sensor cable, cannot exceed 1640 feet (500
meters). See Figure LonWorks Network Topology.
For network lengths that exceed 500 meters (1640 feet), a two-port or three-port
repeater can be used (part numbers 587-450 and 587-455, respectively). This will
allow three separate network lengths of 500 meters.