EXCEL 10 W7750A,B,C CONSTANT VOLUME AHU CONTROLLER
17 74-2958—1
Fig. 8. DIN rail adapters.
The FTT supports polarit
insensitive free topolo
wirin
.
This frees the s
stem installer from wirin
usin
a specific bus
topolo
. T-tap, star, loop, and mixed wirin
topolo
ies are all
supported b
this architecture. The maximum L
ON
W
ORKS
Bus
len
th when usin
a combination of T-tap, star, loop, and bus
wirin
sin
l
terminated
is 1640 ft.
500m
with the maximum
node-to-node len
th of 1312 ft.
400m
. In the event that the
total wire len
th is exceeded, then a Q7740A 2-Wa
Repeater
or a Q7740B 4-Wa
Repeater can be used to allow the
number of devices to be spread out as well as increasin
the
len
th of wire over which the
communicate. The maximum
number of repeaters per se
ment is one
on either side of the
router
. A Q7751A,B L
ON
W
ORKS
Bus Router can also be used
to effectivel
double the maximum L
ON
W
ORKS
Bus len
th.
The advanta
e of usin
the router is that it se
re
ates traffic
to a se
ment while when usin
the repeater, all traffic is
repeated on each se
ment. When utilizin
a doubl
terminated L
ON
W
ORKS
Bus structure, use a continuous dais
-
chain with no stubs or taps from the main backbone, The
maximum L
ON
W
ORKS
Bus len
th is 4593 ft.
1400m
with the
maximum node-to-node len
th of 3773 ft.
1150m
.
FTT networks are ver
flexible and convenient to install and
maintain, but it is imperative to carefull
plan the network
la
out and create and maintain accurate documentation. This
aids in compliance verification and future expansion of the
FTT network. This also keeps unknown or inaccurate wire run
len
ths, node-to-node
device-to-device
distances, node
counts, total wire len
th, inaccurate repeater/router locations,
and misplaced or missin
terminations minimized. Refer to
L
ON
W
ORKS
Bus Wirin
Guidelines form, 74-2865 for complete
description of network topolo
rules.
L
ON
M
ARK
® FUNCTIONAL PROFILE
W7750 Controllers support the L
ON
M
ARK
Functional Profile
number 8030 Roof Top Unit Controller, version 1.0
see Fi
. 9
.
M6857
1
2
3
