Communications; Lon Works Bus Wiring; Lon; On Works Bus Termination - Honeywell Excel 500 Installation Instructions Manual

EXCEL 500/600 INSTALLATION INSTRUCTIONS

COMMUNICATIONS

L W Bus Wiring
ON ORKS
Connection between the Distributed I/O modules and the
CPU are made from the L
XSL511. The L W
ON ORKS
uses transformer isolation so that the bus wiring does not
have a polarity; that is, it is not important which of the two
L W bus terminals are connected to each wire of the
ON ORKS
twisted pair.
The L W bus can be wired in daisy chain, star, loop or
ON ORKS
any combination thereof as long as the maximum wire length
requirements given below are met. The recommended
configuration is a daisy chain with two bus terminations. This
layout allows for maximum L
simple structure presents the least number of possible
problems, particularly when adding on to an existing bus.
Table 16. Doubly-terminated bus specifications
Cable type
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
recommended by Honeywell is the level IV, 22
AWG, solid core, nonshielded cable. Belden part
numbers are 9H2201504 (plenum) and 9D220150
(non-plenum).
IMPORTANT
It is recommended that ferrules not be used to
terminate stranded wires to be inserted in the
Distributed I/O Terminal blocks spring-clamp
terminals.
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 maximum node-to-node distance. If
multiple paths exists, the maximum total wire length is the
total amount of wire used.
Table 17. Free topology (singly-terminated) specifications
Cable type
Belden 85102 1650 ft (500m)
Belden 8471 1300 ft (400m)
Level IV, 22AWG 1300 ft (400m)
JY (St) Y 2x2x0.8 1050 ft (320m)
TIA568A Category 5
825 ft (250m)
24AWG, twisted pair
EN1R-1047GE51 RR0902
W connector module
ON ORKS
bus is a 78-kilobit serial link that
W bus length, and its
ON ORKS
Max. bus length
2700 m (8900 ft)
2700 m (8900 ft)
1400 m (4600 ft)
900 m (3000 ft)
900 m (3000 ft)
Max. node-to- Max. total wire
node distance length
1650 ft (500m)
1650 ft (500m)
1650 ft (500m)
1650 ft (500m)
1500 ft (450m)
IMPORTANT
Do not use different wire types or gauges on the
same L W
ON ORKS
change in line impedance characteristics would
cause unpredictable reflections on the bus.
NOTE: In the event that the limit on the total wire length is
exceeded, then 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 maximum
length 3000 ft (900 m) for each repeater.
On the Excel 500-XCL5010 controller, the L
connections are located on the communication module as
shown in Fig. 78:
1 2 3 4 5 6

LON

BUS
Fig. 78. Excel 500-XCL5010 communication module
L W Bus Termination
ON ORKS
Depending upon the configuration, either one or two
termination modules are required for terminating a L
bus with FTT devices on it. The following two different
L W termination units are available for this purpose:
ON ORKS
•
209541B L W
ON ORKS
79 and Fig. 80) and
•
XAL-Term L W
ON ORKS
module (see Fig. 81), which can be mounted on DIN rails
and in fuse boxes.
Fig. 79. Termination Module 209541B connections for
doubly-terminated FTT network
36
network segment. The step
W
ON ORKS
LON SERVICE BUTTON
POWER, GRN
LON SERVICE, RED
C-BUS TxD, YEL
C-BUS RxD, YEL
RESERVED
C-BUS
TERMINATION
SWITCH
C-BUS
Bus Termination Module (see Fig.
connection and termination
bus
LEDs
W
ON ORKS