Excel 800
Planning
13
EN1B-0375GE51
R0910
L
ON
W
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Bus Cables
Cable type
Max. bus length
Belden 85102 (plenum)
2700 m (8900 ft)
Belden 8471 (non-plenum)
2700 m (8900 ft)
Level IV, 22 AWG
1400 m (4600 ft)
JY (St) Y 2 x 2 x 0.8
900 m (3000 ft)
TIA568A Cat. 5 24AWG, twisted pair
900 m (3000 ft)
Table 18 Doubly-terminated bus specifications
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, non-shielded cable.
Belden part numbers are 9H2201504 (plenum) and
9D220150 (non-plenum).
FTT Specification
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 exist, the maximum total wire length is
the total amount of wire used.
Cable type
Max. node-to-
node distance
Max. total wire
length
Belden 85102
500 m (1650 ft)
500 m (1650 ft)
Belden 8471
400 m (1300 ft)
500 m (1650 ft)
Level IV, 22AWG
400 m (1300 ft)
500 m (1650 ft)
JY (St) Y 2 x 2 x 0.8 320 m (1050 ft)
500 m (1650 ft)
TIA568A Cat. 5
24AWG, twisted pair
250 m (825 ft)
450 m (1500 ft)
Table 19 Free topology (singly-terminated) specifications
NOTICE
Unpredictable reflections on the bus due to step change
in line impedance characteristics!
►
Do not use different wire types or gauges on the same
L
ON
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network segment.
Note
In the event that the limit on the total wire length is
exceeded, the FTT physical layer repeaters (FTT 10A) can
be added to interconnect segments. This increases 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 2 x 2 x 0.8 cable increases the maximum
length 900 m (3000 ft) for each repeater.
Field Device Cables
Cross-sectional area
Type of signal
100 m (300 ft)
(Fig. 40 on p. 29)
one transformer
400 m (1300 ft)
(Fig. 41 on p. 29)
separate
transformers
24 VAC power
1.5 mm
2
(16 AWG)
not allowed for
> 100 m (300 ft)
0…10 V signals
0.081 – 2.08 mm
2
(28 – 14 AWG)
Table 20 Cable sizing for connection of field devices
For wiring field devices see page 29.
