Omron CS1W-RPT01 Manuale Utente

The equation for minimum data link I/O response time is as follows:

Note If the total number of data link words is greater than the maximum number of

words that can be exchanged per data exchange, the maximum data link I/O
response time will be cycle time of PLC at node #7 

×

 3.

In case of the CQM1H, however, the cycle time will be incremented by the
value obtained from dividing the total number of data link words by the maxi-
mum number of words (1,200 words) per time.
For example, if the total number of data link words is 5,000, the result will be
as shown below.

5,000/1,200 = 2.5 (approx. 3)
Cycle time of PLC at node #7 

×

 (1+3)

Noise may increase I/O delays.

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

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.

Input ON delay

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Cycle time of PLC at node #1

15 ms

PLC cycle time at node #7 (See note.)

20 ms (See note.)

Output ON delay

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Total (data link I/O response time)

35 ms

Controller Link Unit transmission processing

 

Program

(1)

(2)

(3)

(4)

Input

Input device

Input ON delay

1 cycle

Program

PLC at node #1

PLC at node #7

Data link transmission

Controller Link Unit transmission processing

Communications 
cycle time

Output device

Output ON 
delay

Output

Data link I/O response time

Peripheral servicing interval

I/O refresh

Previous communica-
tions cycle data

1 cycle

Peripheral servicing interval