Step 2. Determine Required Network Devices; Step 3. Lay Out Communications And Power Wiring; Lonworks Bus Layout - Honeywell Q7300H System Engineering

T7300F/Q7300H SERIES 2000 COMMERCIAL THERMOSTATS AND COMMUNICATING SUBBASES
Step 2. Determine Required Network
Devices
A maximum of 60 nodes can communicate on a single
LonWorks Bus segment. Each LonWorks
comprises one node. If more than 60 nodes are needed, a
Q7751A Router or Q7740 Repeater is necessary. In a
network with Excel 15 devices, a router allows up to 120
controller nodes per network, divided between two
LonWorks Bus segments. A router or repeater allows up
to 120 controller nodes per network, divided between two
LonWorks Bus segments. The router comprises two
nodes (one node on each side of the router). Router and
operator access nodes are not counted in the maximum
controller node totals. All devices are able to talk to each
other through the router.
Multiple operator terminals can be connected to the
LonWorks Bus at the same time. Table 4 summarizes
the LonWorks Bus segment configuration rules.
Refer to the E-Bus Wiring Guidelines, form 74-2865, for a
complete description of network topology rules and
maximum wire lengths. If longer runs are required, use a
Q7740A 2-way or Q7740B 4-way repeater to extend the
length of the LonWorks Bus. Each network segment can
only have one repeater. If more nodes or longer distances
are required, add a router or repeater to limit bus traffic or
boost distance.
Table 4. LonWorks
One LonWorks
Maximum number of Excel 10s
Maximum number of Excel 15s
Two LonWorks Bus Segments; with Excel 15
Controllers, more than 60 devices
One Q7751A,B Router
Maximum number of Excel 15s
Maximum number of Excel 10 RIO devices
Maximum number of Excel 10s (20 per each Excel 15)
Two LonWorks Bus Segments; without Excel 15
Controllers, more than 60 devices
One Q7751A,B Router
Maximum number of Excel 10s (60 per segment)
63-4365
Bus device
Bus Configuration Rules and Device Node Numbers.
Bus Segment
Total
Total
Total
In addition, a 209541B Termination Module may be
required. Refer to the E-Bus Wiring Guidelines, form 74-
2865, and the Excel 10 FTT Termination Module
Installation Instructions form, 95-7554, or if Excel 15s are
present, see Application Step 3. Lay Out Communications
and Power Wiring in the W7760A System Engineering
Guide, form 74-2969.
Step 3. Lay Out Communications and
Power Wiring
LonWorks® Bus Layout
The communications LonWorks
network that uses transformer isolation and differential
Manchester encoding.
The Free Topology Transceiver (FTT) LonWorks
communications Bus supports a polarity insensitive, free
topology wiring scheme, refer to the E-Bus Wiring
Guidelines form, 74-2865, for a complete description of
LonWorks network topology rules.
Fig. 6 shows a typical wiring diagram for the
T7300F/Q7300H in a LonWorks® network. Fig. 7 and 8
show wiring layouts for two doubly daisy-chained
LonWorks Bus segments.
Maximum Number of Controller Nodes 60
60 nodes (minus number of Excel 15s)
4 nodes
60 nodes maximum
Maximum Number of Controller Nodes 112, plus two
nodes for router access.
2 nodes
8 nodes
24 nodes
112 nodes (minus number of RIOs)
122 nodes maximum
Maximum Number of Controller Nodes 120, plus two
nodes for router access.
2 nodes
120 nodes
122 nodes maximum
12
Bus, is a 78-kilobit