EXCEL 10 W7750A,B,C CONSTANT VOLUME AHU CONTROLLER
29 74-2958—1
APPLICATION STEPS
Overview
The seven application steps shown in Table 6 are plannin
considerations for en
ineerin
an Excel 10 W7750 S
stem.
These steps are
uidelines intended to aid understandin
of
the product I/O options, bus arran
ement choices,
confi
uration options and the Excel 10 W7750 Controller role
in the overall EXCEL 5000
OPEN
SYSTEM architecture.
Table 6. Application Steps.
Step 1. Plan the System
Plan the use of the W7750 Controllers accordin
to the
ob
re
uirements. Determine the location, functionalit
and sensor
or actuator usa
e. Verif
the sales estimate of the number of
W7750 Controllers, T7770 and T7560 Wall Modules re
uired
for each model t
pe. Also check the number and t
pe of
output actuators and other re
uired accessories.
When plannin
the s
stem la
out, consider potential
expansion possibilities to allow for future
rowth. Plannin
is
ver
important to be prepared for addin
HVAC s
stems and
controllers in future pro
ects.
T7560 Wall Modules can onl
be hard-wired, the
have no
L
ON
W
ORKS
Bus access. T7770 Wall Modules can be installed
as either hard-wired I/O-onl
devices or additional wirin
can
be run to them
for the L
ON
W
ORKS
Bus network
to allow a
CARE/E-Vision operator terminal to have access to the
L
ON
W
ORKS
Bus. The application en
ineer needs to determine
how man
wall modules, T7770s and T7560s are re
uired. All
T7770 Wall Modules, except the T7770A1006 and the
T7770A1014, can be connected via the L
ON
W
ORKS
Bus
ack.
Also the application en
ineer needs to know how man
T7770s without L
ON
W
ORKS
Bus network connections are
bein
installed on the
ob, and then clearl
document which
wall modules
if an
have network access. This information is
re
uired durin
installation to ensure that the proper number
and t
pe of wires are pulled to the wall modules, and the
buildin
operators are informed about where the
can plu
in
to the L
ON
W
ORKS
Bus network with a portable operator
terminal
see Fi
. 18, 19 and 20
. Refer to Step 4. Prepare
Wirin
Dia
rams for details, about the about the wirin
differences between the two t
pes.
Fig. 18. Connecting the portable operator terminal
to the L
ON
W
ORKS
®
Bus.
The FTT communication wirin
,
L
ON
W
ORKS
Bus
between
controllers is a free topolo
scheme that supports T-tap, star,
loop, and mixed wirin
architecture. Refer to the L
ON
W
ORKS
Bus Wirin
Guidelines form, 74-2865 for complete description
of network topolo
rules. See Application Step 3. La
Out
Communications and Power Wirin
, for more information on
bus wirin
la
out, and see Fi
. 27 throu
h 35 in Application
Step 4. Prepare Wirin
Dia
rams, for wirin
details.
The application en
ineer must review the Direct Di
ital
Control
DDC
ob re
uirements. This includes the Se
uences
of Operation for the W7750 units, and for the s
stem as a
whole. Usuall
there are variables that must be passed
between the W7750 Controllers and other zone controller
s
,
or central plant controller
s
that are re
uired for optimum
s
stem-wide operation. T
pical examples are the TOD Occ/
Unocc si
nal, the outdoor air temperature, the demand limit
control si
nal, and the smoke control mode si
nal.
It is important to understand these interrelationships earl
in
the
ob en
ineerin
process to ensure implemention when
confi
urin
the controllers.
See Application Step 6. Confi
ure
Controllers, for information on the various Excel 10
parameters and on Excel 10 point mappin
.
Step 2. Determine Other Bus Devices
Required
A maximum of 62 nodes can communicate on a sin
le
L
ON
W
ORKS
Bus se
ment. Each W7750
CVAHU
Controller
constitutes one node. If more nodes are re
uired, a Q7751A,B
Router is necessar
. Usin
a router allows up to 125 nodes,
divided between two L
ON
W
ORKS
Bus se
ments. The router
accounts for two of these nodes
one node on each side of the
router
; a Q7750A Excel 10 Zone Mana
er takes one node
and two nodes are available for operator terminal nodes,
leavin
120 nodes available for Excel 10 Controllers. All 120
controllers are able to talk to each other throu
h the router. A
Q7750A Excel 10 Zone Mana
er is re
uired to connect the
L
ON
W
ORKS
Bus to the standard EXCEL 5000
OPEN
S
stem C-Bus. Each Excel 10 Zone Mana
er supports up to
120 Excel 10 Controllers. This limit is set in the Excel 10 Zone
Mana
er database as an absolute maximum.
Step No. Description
1 Plan The S
stem
2 Determine Other Bus Devices Re
uired
3La
Out Communications and Power Wirin
4 Prepare Wirin
Dia
rams
5Order E
uipment
6Confi
ure Controllers
7 Troubleshootin
M15120A
NOTEBOOK PC
LONWORKS BUS
PORT
EIA-232
SERIAL
PORT
Q7752A
SLTA
CABLE
PART
NO. 205979
SHIELDED
INTERFACE
CABLE
EXCEL 10
W7750
CVAHU
CONTROLLER
