Communications Cycle Time; Active Data Links - Omron SYSMAC CS1W-CLK13 Operation Manual

Communications Cycle Time

9-2 Communications Cycle Time
9-2-1

Active Data Links

Calculation Example
4. Specify a value for the maximum node address that is equal to or greater
than the maximum node address in the Controller Link Network.
5. For the CVM1 and CV-series PLCs, always set the System Protect Key
Switch on the CPU Unit to NORMAL. Otherwise, the network parameter
settings will not be stored normally.
This section describes how to calculate the communications cycle time.
The following equations are used to calculate the communications cycle time
when data links are operating.
Token-ring Mode
9.1 × A +1,740 × B + 960 × C + 1,100 × D + 4 × E + 2 × F + 4,800 ( µ s)
Token-bus Mode
9.1 × A +1,300 × B + 290 × C + 320 × D + 4 × E + 2 × F + 2,290 ( µ s)
Note A: Total number of data link words within the network
(total number of words in send areas of all nodes)
B: Number of polled nodes per comm cycle
(value specified in the network parameters)
C: Number of nodes connected to the network
D: Number of nodes that send messages during the
communications cycle
E: Total number of bytes in messages transmitted during the
communications cycle
F: Optical Fiber Cable transmission delay time
H-PCF cable: F = 7 × L µ s (L is the cable length in km.)
GI cable:F = 5 × L µ s (L is the cable length in km.)
The number of bytes in each message differs according to the instruction
being issued, as shown in the following table.
Instruction
Number of words to be sent × 2 +
SEND
18
RECV 18
CMND Number of bytes in command data
+ 10
Communications conditions are as follows:
Transmission distance (with H-PCF cable):
Transmission speed:
Network parameters:
Max node address:
Polled nodes per comm cycle:
Event-frames per comm cycle:
Network configuration:
Total number of data link words:
Nodes that send messages:
Bytes in all messages sent:
When sent
14
Number of words to be received
× 2 + 14
Number of bytes in response
data + 10
Section 9-2
When received
8 km
2 Mbps (fixed)
Defaults
62
4
35
8 nodes
8,000 words
2 nodes
2,012 × 2 bytes
221