C-Bus Connection Procedure; Lon Works Network Interface; Lon; On Works Bus Termination - Honeywell Excel 50 Installation Instructions Manual

C-Bus Connection Procedure

1. Choose a suitable C-Bus cable from Table 18.
IMPORTANT
Make sure that all bus devices connected to the
same C-Bus are set to the same baud rate;
otherwise, proper communication cannot be ensured.
2. Set the DIP switch according to Table 17.
IMPORTANT
The C-Bus must be connected through the individual
controllers (open ring). Star connection is not per-
mitted because uncontrollable line reflections could
occur.
3. Connect the cable shield to C-Bus terminal 4 (Fig. 37).
4. Connect the C+ cable to C-Bus terminal 5 (Fig. 37).
5. Connect the C- cable to C-Bus terminal 6 (Fig. 37).
6. If the max. C-Bus length for the chosen cable (Table 18)
is exceeded:
— Use repeaters to extend to the max. C-Bus length
(see section "
C-Bus Extension by Using Repeaters").
It may take up to two minutes to re-initialize the bus when
adding or removing a controller to/from the C-Bus. During this
time, communication on the C-Bus is lost.
L W Network Interface
ON ORKS
Excel 50 Controllers may be equipped with an application
module (see Table 15) containing an FTT-10A Free Topology
Twisted Pair Transceiver which allows communication with
other device on a L W
ON ORKS
communicate at 78 Kbaud and provide transformer isolation
so that the bus wiring does not have a polarity; that is, it is not
important which of the two bus terminals are connected to
each wire of the twisted pair.
1 2 3 4 5 6

LON

BUS
Fig. 39. LonWorks network connection
FTT devices can be wired in daisy chain, star, loop or any
combination thereof as long as the max. wire length re-
quirements given below are met. The recommended con-
figuration is a daisy chain with two bus terminations. This
layout allows for max. bus length, and its simple structure
presents the least number of possible problems, particularly
when adding on to an existing bus.
network. FTT-10A transceivers
LON SERVICE BUTTON
POWER, GRN
LON SERVICE, RED
C-BUS TxD, YEL
C-BUS RxD, YEL
RESERVED
C-BUS
TERMINATION
SWITCH
(optional)
C-BUS
EXCEL 50 INSTALLATION INSTRUCTIONS
NOTE: A doubly-terminated bus may have stubs of up to
10 ft (3 m) from the bus to each node.
Table 20. Doubly-terminated bus specifications
Belden 85102
Belden 8471
Level IV, 22 AWG
JY (St) Y 2x2x0.8
TIA568A Categ. 5 24AWG, twisted pair
NOTES:
The cable types listed above are as recommended by
Echelon in their FTT-10A User Guide. The cable re-
commended by Honeywell is the level IV, 22 AWG, solid core,
nonshielded cable. Belden part numbers are 9H2201504
(plenum) and 9D220150 (non-plenum).
The FTT specification includes two components that must be
met for proper system operation. The distance from each
transceiver to all other transceivers and to the termination
must not exceed the max. node-to-node distance. If multiple
paths exists, the max. total wire length is the total amount of
wire used.
Table 21. Free topology (singly-terminated) specifications
cable type
Belden 85102
Belden 8471
Level IV, 22AWG
JY (St) Y 2x2x0.8
TIA568A Category 5
24AWG, twisted pair
LEDs
IMPORTANT
Do not use different wire types or gauges on the
same L
in line impedance characteristics would cause
unpredictable reflections on the network.
NOTE: In the event that the limit on the total wire length is
exceeded, FTT physical layer repeaters (FTT 10A)
can be added to interconnect segments and increase
the overall length by an amount equal to the original
specification for that cable type and bus type for each
repeater used. For example, adding repeaters for a
doubly-terminated bus using
JY (St) Y 2x2x0.8 cable increases the max. length
3,000 ft (900 m) for each repeater.
L W Bus Termination
ON ORKS
One or two Termination Modules, part no. 209541B or part
no. XAL-Term, are required for a L
devices on it, depending upon the configuration. See chapter
"LonWorks System Engineering" of LonWorks Mechanisms –
21
cable type
max. node-to-
node distance
1,650 ft (500 m)
1,300 ft (400 m)
1,300 ft (400 m)
1,050 ft (320 m)
825 ft (250 m)
W network segment. The step change
ON ORKS
W
ON ORKS
EN1B-0101GE51 R1105D
max. bus length
2,700 m (8,900 ft)
2,700 m (8,900 ft)
1,400 m (4,600 ft)
900 m (3,000 ft)
900 m (3,000 ft)
max. total wire
length
1,650 ft (500 m)
1,650 ft (500 m)
1,650 ft (500 m)
1,650 ft (500 m)
1,500 ft (450 m)
Bus with FTT