Omron CJ1W-CLK21-V1, CVM1-CLK21, CS1W-RPT01, C200HW-CLK21, CQM1H-CLK21 Calculation Example

Data Link I/O Response Time			Section 8-3
	PLCs	Words per data exchange
	CS/CJ-series PLCs	Approx. 7,800 words
	CVM1 and CV-series PLCs	Approx. 3,700 words
	C200HX/HG/HE PLCs	Approx. 4,000 words
	CQM1H-series PLCs	Approx. 1,200 words

Note 1. Use the above equations only if only one Controller Link Unit is mounted on the PLC. If other CPU Bus Units are mounted on the PLC, obtain the refresh times for each CPU Bus Unit and add to the above equations.

2.The execution of some items takes precedence over data link area refresh- ing. For example, data link area refreshing will not take place during exe- cution of the SEND(192), RECV(193), or FAL(006) instruction.

8-3-3 Calculation Example

The data links of the Controller Link Unit require a slight time delay from the time the data link area of one node is changed until this change is reflected in the data link area at another node. This time delay is called the data link I/O response time. The following is a calculation example of the maximum and minimum I/O response times for the system configuration shown below.

PLC

Input

C	PLC
L
K
#1

Input LRXXXX

		CLK: Controller Link Unit
C		System configuration
L
		Baud rate:	2 Mbps
K
#1		Maximum node address:	32
		Number of polled nodes per comm cycle:	4
		Number of event-frames per comm cycle:	35
		Nodes in network:	8 nodes
		Nodes in data links:	8 nodes
LRXXXX	Output	Words sent in area 1:	8 words per node
		Words in area 2:	16 words per node

No messages communications are performed.

A single Controller Link Unit is mounted to each

CPU Rack.

The data link I/O response time depends on the communications cycle time, input ON delay, output ON delay, and the cycle times of the PLCs involved. The values are detailed below.

Communications Cycles	Communications cycle time =
Time	10 ⋅ (8 + 16) ⋅ 8 + 600 ⋅ 4 + 290 ⋅ 8 + 320 ⋅ 0 + 4 ⋅ 0 + 3,290
	= 9,930 ∝s ≅ 9.9 ms
Input ON Delay	The input ON delay is the time it takes for an input device to turn ON an input
	to the PLC after receiving an input signal. In this system the input ON delay is
	1.5 ms.
Output ON Delay	The output ON delay is the time it takes for an output device to turn ON an
	output signal after receiving an output from the PLC. In this system the output
	ON delay is 15 ms.
Cycle Times	The cycle time of the PLC at node #1 is 25 ms.
	The cycle time of the PLC at node #7 is 10 ms.

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