EXCEL 10 W7750A,B,C CONSTANT VOLUME AHU CONTROLLER
109 74-2958—1
Appendix D. Q7750A Excel 10 Zone Manager
Point Estimating Guide.
Memor
size approximation is shown below:
all sizes in
b
tes
When
memory size
is less than 110,000 b
tes, the size is OK.
When
memory size
is between 110,000 and 128,000 b
tes,
the application ma
be too lar
e. The user must expect to
reduce the application complexit
, reduce the number of
attached Excel 10s or distribute the Excel 10s over more than
one Zone Mana
er.
When
memory size
is
reater than 128,000, the size is too
lar
e. The application size must be reduced as described
above.
Approximate Memory Size Estimating Procedure.
1.
Determine the number of points per controller re
uired
at the Central
for example, XBS
.
NOTE: All remainin
points that are not mapped can
be accessed throu
h the
Direct Access
feature.
2.
Calculate the number of Excel 10 Zone Mana
er pro-
ram points that are used in control lo
ic and in the
switchin
table.
3.
Estimate the pro
ram complexit
of the Zone Mana
er
one of three levels
.
a. No time pro
rams, control lo
ic, or switchin
tables.
b. 10K of control lo
ic
one time pro
ram, five
switchin
tables, and five control loops
.
c. 20K of control lo
ic
multiple time pro
rams, ten
switchin
tables, and ten control loops
.
Use Fi
. 51 to determine the number of Excel 10s that
can be connected to the Zone Mana
er.
NOTE: More than 60 Excel 10s re
uires a Router.
4.
Repeat for each Q7750A Excel 10 Zone Mana
er in a
pro
ect.
Fig. 51. Point capacity estimate for Zone Manager.
The exact e
uation for calculatin
memor
size follows:
Memor
size = 21,780
+ 4096
in case of a time pro
ram
.
+ CARE Control Pro
ram.
+ 14 x time points x Excel 10 units.
+ 50 x Excel 10 units.
+ map complexit
x Excel 10 units x mapped points.
+ 57 x C-Bus points.
+ 7488 x Excel 10 t
pes.
Where:
Time points = number of switch points in time pro
ram
per Excel 10.
Excel 10 units =number of attached Excel 10s.
C-Bus points = includin
mapped points and others; for
example, remote points.
Mapped points = number of mapped points per Excel 10,
includin
One-to-Man
and
Man
-to-One mechanism.
Excel 10 t
pes = number of different Excel 10 t
pes
currentl
three
Map complexit
=
20 =usin
One-to-Man
and not usin
points
with read/write.
30 = avera
e.
45 = man
points with read/write abilit
.
20 60 120
600
700
800
900
600
700
800
900
920
765
610
585
740
895
NUMBER OF
C-BUS POINTS
(EXCEL 10
MAPPED
POINTS
PLUS ZONE
MANAGER
POINTS)
(OR LESS) (ADD ROUTER)
NUMBER OF EXCEL 10s
(C)
(A)
NUMBER OF
C-BUS POINTS
(EXCEL 10
MAPPED
POINTS
PLUS ZONE
MANAGER
POINTS)
NO TIME PROGRAM,
NO CONTROL LOOPS,
NO SWITCHING TABLES.
20K CONTROL PROGRAM
(I.E., MULTIPLE TIME PROGRAMS,
10 CONTROL LOOPS,
10 SWITCHING TABLES.)
10K CONTROL PROGRAM
(FOR EXAMPLE,
1 TIME PROGRAM,
5 CONTROL LOOPS,
5 SWITCHING TABLES.)
(B)
M8729
