Omron C200HW-CLK21, CVM1-CLK21, CS1W-RPT01, CJ1W-CLK21-V1, CQM1H-CLK21, CS1W-CLK21-V1 Time Case

Data Link I/O Response Time Section 8-3

CVM1, CV-series, CS/CJ-series PLCs Under Synchronous Operation or C200HX/HG/ HE and CQM1H-series PLCs

Maximum I/O Response The maximum data link I/O response time is calculated for four cases.

Time

Case 1

The following diagram illustrates the data flow that will produce the maximum data link I/O response time when the cycle time of the PLC at nodes #1 and 7 are greater than the communications cycle time.

Input

		Input device
	Input ON delay
X			1 cycle
	(1)

Program

X

(2)

Communications cycle time

I/O refresh

Data exchange

PLC at node #1
Controller Link Unit
transmission processing
	Data link transmission
X (3) X
		Controller Link Unit
Previous communica		transmission processing
tions cycle data

X(4)

PLC at node #7	Program
	1 cycle
	Output device
	Output ON delay
Data link I/O response time	Output

There are four points shown in the diagram above where processing is delayed, increasing the data link I/O response time.

1,2,3... 1. The input arrives in the PLC just after I/O refreshing, causing a delay of up to one cycle before the input is read into the PLC.

2.Data exchange occurs just after the PLC at node #1 passes the token that makes it the polling node, causing a delay of up to one communications cy- cle time before the data is transferred in data link processing.

3.At node #7, data from the previous data exchange is still being transferred, causing a delay of up to one cycle before the input is read into the PLC.

4.The data transferred in data link processing arrives at the PLC at node #7 after data exchange, so the data will not be read into the PLC until the next data exchange, causing a delay of up to 1 to 2 cycle.

The maximum number of words that can be exchanged in a single data ex- change is approx. 7,800 words for CS/CJ-series PLCs, approx. 3,700 words for CVM1 and CV-series PLCs, approx. 4,000 for C200HX/HG/HE PLCs, and approx. 1,200 words for CQM1H-series PLCs.

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