EXCEL 10 W7761A INPUT/OUTPUT DEVICE

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.

 

920

 

900

 

800

NUMBER OF

765

C-BUS POINTS (EXCEL 10 MAPPED

POINTS

700

PLUS ZONE

 

MANAGER

 

POINTS)

 

610

600

(A)NO TIME PROGRAM, NO CONTROL LOOPS, NO SWITCHING TABLES.

(B)10K CONTROL PROGRAM (I.E., 1 TIME PROGRAM, 5 CONTROL LOOPS,

5 SWITCHING TABLES.)

(C)20K CONTROL PROGRAM

(I.E., MULTIPLE TIME PROGRAMS, 10 CONTROL LOOPS,

10 SWITCHING TABLES.)

900

895

800

NUMBER OF

740C-BUS POINTS (EXCEL 10

MAPPED

700POINTS PLUS ZONE MANAGER POINTS)

600

585

20

60

(OR LESS)

(ADD ROUTER)

120

NUMBER OF EXCEL 10s

 

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.

71

74-2699

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Image 71
Honeywell W7761A Approximate Memory Size Estimating Procedure, Fig. D-1. Point capacity estimate for Zone Manager