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13. 2.
Guideline of the Response delay between the Gateway and the Motor Control Unit
The gateway unit communicates with the motor controller (LEC) to read the controller status and
commands the controller. The time for the communication causes delay in the response.
Please take this into consideration when selecting the PLC program.
Communication to read the motor controller status
The gateway unit communicates one by one in order. The communication time is approximately 30ms
per unit. When reading of numerical data is validated during Numerical data input mode or data rewrite
mode, it takes another 30ms for communicating with valid controller (LEC).
Communication for commanding the motor controller
When rewrite of the remote I/O and the register is commanded by Profibus master, it takes 30ms for
communicating with the target controller (LEC).
Response delay depends on the number of the connected motor controllers (LEC) and rewrite
frequency.
Ex. 1)
Response time guideline when four controllers are connected in step data input mode.
4 pcs. × approx. 30ms
＝
Approx. 120ms
＋
α
[
α
：
Communication time to rewrite the remote I/O and the register]
Ex. 2)
Response time guideline when twelve controllers are connected in step data input mode.
5 pcs. × approx. 30ms
＝
Approx. 150ms
＋
α
[
α
：
Communication time to rewrite the remote I/O and the register]
Ex. 3)
Response time guideline when 5 controllers are connected in numerical data input mode (3
controllers are valid for reading numerical data).
5 pcs. × approx. 30ms + 3pcs. x approx. 30ms
＝
Approx. 240ms
＋
α
[
α
：
Communication time to rewrite the remote I/O and the register]
※
This response time does not include the response time of Profibus and motor controller (LEC), and
processing time of PLC.
PLC
Gateway
Unit
Motor controller
（
LEC
）
Motor controller
（
LEC
）
Motor controller
（
LEC
）
Profi Bus
Communication between the
gateway unit and the controller
