Honeywell W7761A - Manual (Page 71)

EXCEL 10 W7761A INPUT/OUTPUT DEVICE
71 74-2699
Appendix D. Q7750A Excel 10
Zone Manager Point Estimating Guide.
Memory size approximation is shown below: (all sizes in bytes)
When memory size is less than 110,000 bytes, the size is OK.
When memory size is between 110,000 and 128,000 bytes, the application may be too large. The user must expect to reduce
the application complexity, reduce the number of attached Excel 10s or distribute the Excel 10s over more than one Zone
Manager.
When memory size is greater than 128,000, the size is too large. The application size must be reduced as described above.
Approximate Memory Size Estimating Procedure.
1. Determine the number of points per controller required at the Central (for example, XBS).
NOTE: All remaining points that are not mapped can be accessed through the Direct Access feature.
2. Calculate the number of Excel 10 Zone Manager program points that are used in control logic and in the switching table.
3. Estimate the program complexity of the Zone Manager (one of three levels).
a. No time programs, control logic, or switching tables.
b. 10K of control logic (one time program, five switching tables, and five control loops).
c. 20K of control logic (multiple time programs, ten switching tables, and ten control loops).
Use Fig. D-1 to determine the number of Excel 10s that can be connected to the Zone Manager.
NOTE:
More than 60 Excel 10s requires a Router.
4. Repeat for each Q7750A Excel 10 Zone Manager in a project.
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
(I.E., 1 TIME PROGRAM,
5 CONTROL LOOPS,
5 SWITCHING TABLES.)
(B)
M8729
Fig. D-1. Point capacity estimate for Zone Manager.
The exact equation for calculating memory size follows:
Memory size = 21,780
+ 4096 (in case of a time program).
+ CARE Control Program.
+ 14 x time points x Excel 10 units.
+ 50 x Excel 10 units.
+ map complexity x Excel 10 units x mapped points.
+ 57 x C-Bus points.
+ 7488 x Excel 10 types.
Where:
Time points = number of switch points in time program per Excel 10.
Excel 10 units = number of attached Excel 10s.
C-Bus points = including mapped points and others; for example, remote points.
Mapped points = number of mapped points per Excel 10,
including One-to-Many and Many-to-One
mechanism.
Excel 10 types = number of different Excel 10 types (currently three)
Map complexity =
20 = using One-to-Many and not using
points with read/write.
30 = average.
45 = many points with read/write ability.