KEYENCE N-400 - Manual (Page 125)

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Chapter 6 PLC Link
6
6.5 Communication Time
Even in PLC link mode, the RS-485 communication between the N-400 and each
BL series is regarded as the same as standard mode serial communication. (
➮ See
pp. 83 to 85.)
The time required for the RS-232C communication between the N-400 and the
PLC is described below:
This communication time may change depending on the PLC’s scan time and the
model of the PLC.
■ Time required for RS-232C data transmission in PLC link mode
The time required for data transmission from the N-400 to the PLC is as follows:
This time duration corresponds to the “RS-232C data transmission time in multi-
drop link mode” (B) described on p. 84. To obtain the total communication time,
add the “RS-485 data transmission time” (A) described on p. 82.
* When the RS-232C communication baud rate is 9600 bps:
■ Communication time to start reading using reading trigger area
To control the BL series’ reading operation using the reading trigger area, enter the
trigger ON command on the PLC, and obtain the time duration until the command
is received by the N-400.
This time duration corresponds to the “RS-232C command transmission time”(C)
described on p. 84.
To obtain the total communication time, add the “RS-485 command transmission
time” (D + b) described on p. 84.
* When the RS-232C communication baud rate is 9600 bps:
Number of data digits MELSEC-A SYSMAC-C KV(KV mode)
10 Approx. 300 ms Approx. 350 ms Approx. 500 ms
20 Approx. 350 ms Approx. 400 ms Approx. 750 ms
32 Approx. 400 ms Approx. 500 ms Approx. 1050 ms
Number of MELSEC-A SYSMAC-C KV(KV mode)
connected BL series
1 Approx. 150 ms Approx. 150 ms Approx. 100 ms
31 Approx. 400 ms Approx. 600 ms Approx. 1.5 s