Daikin D-BACS, Design Manual

Page: 262 / 376

12.4 Outline of Functions 245
Interface for use in LONWORKS
®
<Rough Estimate of Number of Groups Connected >
(Assuming that acknowledged service is 10 items per
second on a 30-second interval data collection cycle.)
- Acknowledged Service (possible communication volume): 10 items/second
This is one of the performance features of a Interface for LONWORKS
®
. It can process 10 items per second.
- 30-second interval data collection cycle
This is the time interval whereby device data (status) is collected from the central monitoring panel. In this case, the
data regarding the connected A/C units is collected in 30 seconds. This figure differs with respect to the specifications
of the central monitoring panel.
- Interface for LONWORKS
®
performance
...
Acknowledged Service: 10 items/second (fixed value)
- Central Monitoring Panel performance
...
30-second data collection cycle
10 items per second being collected for 30 seconds translates into a total of 300 control items.
T = 10
×
30 = 300 items
Number of control items per group: Assuming the number of items per group is 23, the number of groups connectable
is 13.
n = T
÷
(No. of control items per group) = 300
÷
23 = 13 groups
- Interface for LONWORKS
®
performance ... Acknowledged Service: 10 items/second (fixed value)
- Central Monitoring Panel performance ... 60-second data collection cycle
10 items per second being collected for 60 seconds translates into a total of 600 control items.
T = 10
×
60 = 600 items
Number of control items per group: Assuming the number of items per group is 23, the number of groups connectable
is 26
n = T
÷
(No. of control items per group) = 600
÷
23 = 26 groups
- Interface for LONWORKS
®
performance
...
Acknowledged Service: 10 items/second (fixed value)
- Central Monitoring Panel performance ... 120-second data collection cycle
10 items per second being collected for 120 seconds translates into a total of 1,200 control items.
T = 10
×
120 = 1,200 items
Number of control items per group: Assuming the number of items per group is 23, the number of groups connectable
is 52
n = T
÷
(No. of control items per group) = 1,200
÷
23 = 52 groups
Control and Monitoring Items
n (individual groups)
Max. number of
groups connected
Remarks
23 items (All) 13 groups
- One LON can monitor up to 300 items.
- The maximum number of control and monitoring items is 23 per A/
C unit. If the number of control and monitoring items per A/C unit is
assumed as ‘n’, the number of A/C groups connectable would be:
<Note: The maximum No. of A/C groups is 64.>
20 items 15 groups
18 items 16 groups
16 items 18 groups
15 items 20 groups
12 items 25 groups
10 items 30 groups
4 items 64 groups